View source for Timeline of binary prefixes

{{short description|none}} <!-- "none" is preferred when the title is sufficiently descriptive; see [[WP:SDNONE]] -->
{{Use mdy dates|date=January 2012}}
This '''timeline of binary prefixes''' lists events in the history of the evolution, development, and use of [[unit of measurement|units of measure]] that are germane to the definition of the [[binary prefixes]] by the [[International Electrotechnical Commission]] (IEC) in 1998,<ref>{{cite book|publisher=International Electrotechnical Commission|date=January 1999|id=IEC 60027-2|title=Amendment 2: Letter symbols to be used in electrical technology – Part 2: Telecommunications and electronics}}</ref><ref>{{cite web|url=http://physics.nist.gov/cuu/Units/binary.html|title=Prefixes for binary multiples|work=The NIST Reference on Constants, Units, and Uncertainty|archive-url=https://web.archive.org/web/20240324182918/http://physics.nist.gov/cuu/Units/binary.html|archive-date=2024-03-24|url-status=dead}}</ref> used primarily with units of [[information]] such as the [[bit]] and the [[byte]].

Historically, computers have used many systems of internal data representation,<ref>{{cite journal |title= Chapter III, Analysis and Trends |journal= Ballistic Research Laboratories Report No. 1115 |date=March 1961 |page=1027 |quote=Of 187 different relevant systems, 131 utilize a straight binary system internally, whereas 53 utilize the decimal system (primarily [[binary-coded decimal|binary coded decimal]]) and 3 systems utilize a binary-coded alphanumeric system of notation. |url= http://ed-thelen.org/comp-hist/BRL61analysis.html#STORAGE}}</ref> methods of operating on data elements, and data addressing. Early [[decimal computer]]s included the [[ENIAC]], [[UNIVAC&nbsp;1]], [[IBM 702]], [[IBM 705]], [[IBM 650]], [[IBM 1400 series]], and [[IBM 1620]]. Early binary addressed computers included [[Zuse Z3]], [[Colossus computer|Colossus]], [[Whirlwind (computer)|Whirlwind]], [[AN/FSQ-7]], [[IBM 701]], [[IBM 704]], [[IBM 709]], [[IBM 7030]], [[IBM 7090]], [[IBM 7040]], [[IBM System/360]] and [[Programmed Data Processor|DEC PDP series]].

Decimal systems typically had memory configured in whole decimal multiples, e.g., blocks of 100 and later {{val|1,000}}. The unit abbreviation '{{blue|K}}' or '{{blue|k}}' if it was used, represented multiplication by {{val|1,000}}. Binary memory had sizes of powers of two or small multiples thereof. In this context, '{{brown|K}}' or '{{brown|k}}' was sometimes used to denote multiples of {{val|1,024}} units or just the approximate size, e.g., either '64K' or '65K' for {{val|65,536}} (2<sup>16</sup>).

{{TOC limit|2}}

== 1790s ==
=== 1793 ===
* The French ''Commission temporaire de Poids & Mesures rêpublicaines'', ''Décrets de la Convention Nationale'', proposes the binary prefixes ''[[double (binary prefix)|double]]'' and ''[[demi (binary prefix)|demi]]'', denoting a factor of 2 (2<sup>1</sup>) and {{frac|2}} (2<sup>−1</sup>), respectively, in 1793.<ref name="CTPM_1793">{{cite book |title= Instruction abrégée sur les mesures déduites de la grandeur de la Terre; uniformes pour toute la Rêpublique, et sur les Calculs relatifs à leur division décimale |author= Commission temporaire de Poids & Mesures rêpublicaines, En exécution des Décrets de la Convention Nationale |publisher= De l'imprimerie nationale exécutive du Louvre |edition= original |location=Paris, France |language=fr |date=1793 |url=https://books.google.com/books?id=QwEOAAAAQAAJ |access-date=2015-10-09}}</ref>

=== 1795 ===
* The prefixes ''[[double (binary prefix)|double]]'' and ''[[demi (binary prefix)|demi]]''<ref name="fr">{{cite web |title=La Loi Du 18 Germinal An 3 – Décision de tracer le mètre, unité fondamentale, sur une règle de platine. Nomenclature des "mesures républicaines". Reprise de la triangulation. |url= http://histoire.du.metre.free.fr/fr/Pages/Sommaire/06.htm |language=fr |publisher= histoire.du.metre.free.fr |access-date= 2015-10-12}}</ref> are part of the original [[metric system]] adopted by France (with kilo for 1000) in 1795. These were not retained when the [[decimal|decadic]] [[SI prefix]]es were internationally adopted by the 11th [[Conférence générale des poids et mesures|CGPM conference]] in 1960.

== 1870s ==
* Metric prefix "{{blue|mega-}}" established in 1873.

== 1930s ==
* Metric prefixes "{{blue|kilo-}}" (established 1795) and "{{blue|mega-}}" (established 1873) are widely used as decimal multipliers 1,000 and 1,000,000 for units of frequency and impedance in the electronics industry.<ref>{{Cite journal |author-first=George |author-last=Grammer |date= January 1933 |title= Rationalizing the Autodyne |journal=[[QST]] |quote=The 7000- and 14,000-kc. grid coils are wound with No. 18 enameled wire ...; R1–5 megohms |url=https://www.rfcafe.com/references/qst/rationalizing-autodyne-january-1933-qst.htm}}</ref><ref>{{cite web |url= http://tubecollectors.org/archives/gamma.pdf |title=HK-354 Gammatron Advertisement |website=Tubecollectors.org |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160817015013/http://tubecollectors.org/archives/gamma.pdf |archive-date=2016-08-17 |url-status=dead}}</ref>
* The Committee of the ''Verband Deutscher Elektrotechniker'' publishes suggested names and symbols for the metric prefixes with decimal meaning, i.e., {{blue|giga}} ({{blue|G}}&nbsp;=&nbsp;10<sup>9</sup>) and {{blue|tera}} ({{blue|T}}&nbsp;=&nbsp;10<sup>12</sup>).<ref>{{cite journal |author=G.W.O.H. |title=Multiples and sub-multiples of ten |journal=The Wireless Engineer |volume=IX |issue=104 |date=May 1932 |page=252 |url=https://worldradiohistory.com/UK/Experimental-Wireless/30s/Wireless-Engineer-1932-05-S-OCR.pdf}}</ref>

== 1940s ==
=== 1943–1944 ===
* [[John Tukey|J. W. Tukey]] coins the word "bit" as an abbreviation of "binary digit".<ref name="TheJargonFile">{{cite web |title= Bit: n.: from the mainstream meaning and "Binary digIT" |website=Catb.org |url= http://catb.org/~esr/jargon/html/B/bit.html |access-date= 2016-06-23}}</ref>

=== 1947 ===
* "The [[Whirlwind I|Whirlwind I Computer]] is planned with a storage capacity of {{val|2,048}} numbers of 16 binary digits each."<ref>{{cite web |title= Project Whirlwind (Device 24-x-3): Report R-127 |website=Bitsavers.org |url= http://www.bitsavers.org/pdf/mit/whirlwind/R-series/R-127_Whirlwind_I_Computer_Block_Diagrams_Volume_1_Sep47.pdf |access-date= 2016-06-23}}</ref>

=== 1948 ===
* Tukey's "bit" is referenced in the work of information theorist [[Claude Shannon]].<ref name=TheJargonFile/>

== 1950s ==
* In the 1950s, "1 {{blue|kilo}}bit" meant {{val|1000}} bits:<ref name="Waldrop_2002">{{cite web |title= Mitch Waldrop / Waldrop Revolution |type= Waldrop Lecture transcript |date= 2002-10-21 |editor-first1=Len |editor-last1= Tristik |editor2=Linda |editor-first3=Karyn |editor-last3=Wolfe |publisher= [[Computer History Museum]] |id=CHMP-03 |url= http://archive.computerhistory.org/resources/text/CHM_Lecture_transcripts/Waldrop%20Lecture%20Transcript.doc |access-date= 2015-10-27 |archive-url= https://web.archive.org/web/20070927225824/http://archive.computerhistory.org/resources/text/CHM_Lecture_transcripts/Waldrop%20Lecture%20Transcript.doc |archive-date= 2007-09-27 |url-status= dead}}</ref><ref name="CHM">{{cite web |title= Computer History Museum's Stretch collection |date= 2004 |url= http://archive.computerhistory.org/stretch |access-date= 2015-10-27 |archive-url= https://web.archive.org/web/20070127201237/http://archive.computerhistory.org/stretch/ |archive-date= 2007-01-27 |url-status= dead}}</ref>
** "In the '50s, amazingly enough—and only total coincidence—I actually was given the job of writing the operational specifications [...] for what was called cross telling. They handed me this thing and said, 'You're going to define how the hand-over process works between direction centers', [...] and I had no idea what they were talking about. But we had [...] one-kilobit lines connecting the direction centers and I thought, 'Good God! {{val|1000}} bits a second. Well, we'll surely be able to figure out something to do with that.{{'"}} — Saverah Warenstein, former programmer at Lincoln Laboratory, IBM<ref name="Waldrop_2002"/>

=== 1952 ===
* The first [[magnetic core memory]], from the [[IBM 405]] Alphabetical Accounting Machine, is tested successfully in April 1952. (The image shows 10&nbsp;×&nbsp;12 cores; presumably one of 8)<ref>{{cite web |title= Core Memory |website= Columbia.edu |url= https://www.columbia.edu/cu/computinghistory/core.html |access-date= 2024-07-06}}</ref>
** "Teaming up with a more experienced engineer, [Mike Haynes] built a core memory with just enough capacity to store all the information in an IBM [[punched card]]: 960 bits in an 80&nbsp;×&nbsp;12 array. In May 1952 it was successfully tested as a data buffer between a Type 405 alphabetical accounting machine and a Type 517 [[summary punch]]. This first functional test of a ferrite core memory was made in the same month that a four-times smaller 16&nbsp;×&nbsp;16-bit ferrite core array was successfully tested at MIT."<ref>{{cite book |title= Building IBM: Shaping an Industry and Its Technology |first= Emerson W. |last=Pugh |page=209 |url= https://books.google.com/books?id=Bc8BGhSOawgC&pg=RA1-PA209 |access-date=2016-06-23|isbn= 9780262161473 |year= 1995 |publisher= MIT Press }}</ref>
* The [[IBM 701]], a binary-addressed computer containing 72 [[Williams tube]]s of {{val|1024}} bits each, is released in April.<ref>{{cite web |title=IBM 701 |website=Thocp.net |date=2002-02-26 |url= http://www.thocp.net/hardware/ibm_701.htm |access-date=2016-06-23}}</ref><ref>{{cite web |title= The IBM 701 |website= Columbia.edu |date= 2006-05-12 |url= https://www.columbia.edu/cu/computinghistory/701.html |access-date=2024-07-06}}</ref>
** ''Principles of Operation Type 701''<ref>{{cite web |title= Principles of Operation Type 701 |website= Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/701/24-6042-1_701_PrincOps.pdf |access-date=2016-06-23}}</ref> does not use prefixes with lengths of words or size of storage. For example, it specifies that memory tubes hold {{val|2048}} words each.<ref>{{cite web |title=IBM Archives: IBM 706 Electrostatic storage unit |website= 03.ibm.com |date= January 23, 2003 |url= http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx06.html |access-date=2016-06-23 |archive-url= https://web.archive.org/web/20160703033432/http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx06.html |archive-date= 2016-07-03 |url-status= dead}}</ref><ref>{{cite web |title=IBM Archives: IBM 731 Magnetic drum reader/recorder |website= 03.ibm.com |url= http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx31.html |access-date= 2016-06-23|date= January 23, 2003 |archive-url= https://web.archive.org/web/20160703033427/http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx31.html |archive-date= 2016-07-03 |url-status= dead}}</ref>
** The IBM 737 optional magnetic core storage stores {{val|4,096}} 36-bit words.<ref>{{cite web |title= IBM Archives: IBM 737 Magnetic core storage unit |website= 03.ibm.com |date= 1954-10-01 |url= http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx37.html |access-date= 2016-06-23 |archive-url= https://web.archive.org/web/20160703015258/http://www-03.ibm.com/ibm/history/exhibits/701/701_1415bx37.html |archive-date= 2016-07-03 |url-status= dead}}</ref> Each plane stored 64&nbsp;×&nbsp;64 = {{val|4,096}} bits.<ref>{{cite web |title= 737 Magnetic Core Storage: Customer Engineering Reference Manual |website= Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/704/223-6818_704_CE_Manual/737_Core_CE_Sep58.pdf |page=60{{hyphen}}16 |access-date= 2016-06-23}}</ref>

=== 1955 ===
* The [[IBM 704]] (a binary machine) manual uses decimal arithmetic for powers of two, without prefixes<ref>{{cite web |title=704 Electronic Data Processing Machine |website= Bitsavers.org |url= http://www.bitsavers.org/pdf/ibm/704/24-6661-2_704_Manual_1955.pdf |access-date= 2016-06-23}}</ref>
** "Magnetic [[core memory|core storage]] units are available with capacities of either {{val|4,096}} or {{val|32,768}} core storage registers; or two magnetic core storage units, each with a capacity of {{val|4,096}} core storage registers, may be used. Thus, magnetic core storage units are available to give the calculator a capacity of {{val|4,096}}, {{val|8,192}}, or {{val|32,768}} core storage registers."
** "Each drum has a storage capacity of {{val|2048}} words."

=== 1956 ===
* The [[IBM 702]] (a decimally addressed machine)  Preliminary Manual of Information uses decimal arithmetic for powers of ten, without prefixes.<ref>{{cite web |title=Electronic Date Processing Machines: Type 702 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/702/22-6173-1_702prelim_Feb56.pdf |access-date=2016-06-23}}</ref>
** "Electrostatic memory is the principal storage medium within the machine. It consists of cathode ray tubes which can store up to {{val|10,000}} characters of information in the form of electrostatic charges ... Additional storage, as required, may be provided through the use of magnetic drum storage units, each having a capacity of {{val|60,000}} characters."
** "A character may be a letter of the alphabet, a decimal number, or any of eleven different punctuation marks or symbols used in report printing."
** "Each one of the {{val|10,000}} positions of memory is numbered from {{val|0000}} to {{val|9999}} and each stored character must occupy one of these positions." (page 8)
* The word '''[[byte]]''', meaning eight bits, is coined by Dr. [[Werner Buchholz]] in June 1956, during the early design phase for the [[IBM 7030|IBM Stretch]] computer.<ref name="Bemer_2000">{{cite web |title=Why is a byte 8 bits? Or is it? |author-first=Robert William |author-last=Bemer |author-link=Robert William Bemer |date=2000-08-08 |work=Computer History Vignettes |url=http://www.bobbemer.com/BYTE.HTM |access-date=2017-04-03 |url-status=dead |archive-url=https://web.archive.org/web/20170403130829/http://www.bobbemer.com/BYTE.HTM |archive-date=April 3, 2017 |quote=[...] With [[IBM]]'s [[IBM STRETCH|STRETCH]] computer as background, handling 64-character words divisible into groups of 8 (I designed the character set for it, under the guidance of Dr. [[Werner Buchholz]], the man who DID coin the term "[[byte]]" for an 8-bit grouping). [...] The [[IBM System 360|IBM 360]] used 8-bit characters, although not ASCII directly. Thus Buchholz's "byte" caught on everywhere. I myself did not like the name for many reasons. [...] |df=mdy-all }}</ref><ref name="Buchholz_1956">{{cite book |title=The Link System |chapter=7. The Shift Matrix |author-first=Werner |author-last=Buchholz |author-link=Werner Buchholz |date=1956-06-11 |id=[[IBM Stretch|Stretch]] Memo No. 39G |publisher=[[IBM]] |pages=5–6 |chapter-url=http://archive.computerhistory.org/resources/text/IBM/Stretch/pdfs/06-07/102632284.pdf |access-date=2016-04-04 |url-status=dead |archive-url=https://web.archive.org/web/20170404152534/http://archive.computerhistory.org/resources/text/IBM/Stretch/pdfs/06-07/102632284.pdf |archive-date=April 4, 2017 |quote=[...] Most important, from the point of view of editing, will be the ability to handle any characters or digits, from 1 to 6 bits long [...] the Shift Matrix to be used to convert a 60-bit [[word (computer architecture)|word]], coming from Memory in parallel, into [[character (computing)|character]]s, or "[[byte]]s" as we have called them, to be sent to the [[serial adder|Adder]] serially. The 60 bits are dumped into [[magnetic core]]s on six different levels. Thus, if a 1 comes out of position 9, it appears in all six cores underneath. [...] The Adder may accept all or only some of the bits. [...] Assume that it is desired to operate on 4-bit [[decimal digit]]s, starting at the right. The 0-diagonal is pulsed first, sending out the six bits 0 to 5, of which the Adder accepts only the first four (0–3). Bits 4 and 5 are ignored. Next, the 4 diagonal is pulsed. This sends out bits 4 to 9, of which the last two are again ignored, and so on. [...] It is just as easy to use all six bits in [[alphanumeric]] work, or to handle bytes of only one bit for logical analysis, or to offset the bytes by any number of bits. [...] |df=mdy-all }}</ref><ref name="Buchholz_1977">{{cite journal |author-last=Buchholz |author-first=Werner |author-link=Werner Buchholz |title=The Word "Byte" Comes of Age... |journal=[[Byte Magazine]] |date=February 1977 |volume=2 |issue=2 |page=144 |url=https://archive.org/stream/byte-magazine-1977-02/1977_02_BYTE_02-02_Usable_Systems#page/n145/mode/2up |quote=[...] The first reference found in the files was contained in an internal memo written in June 1956 during the early days of developing [[IBM Stretch|Stretch]]. A [[byte]] was described as consisting of any number of parallel bits from one to six. Thus a byte was assumed to have a length appropriate for the occasion. Its first use was in the context of the input–output equipment of the 1950s, which handled six bits at a time. The possibility of going to 8-bit bytes was considered in August 1956 and incorporated in the design of Stretch shortly thereafter. The first published reference to the term occurred in 1959 in a paper "Processing Data in Bits and Pieces" by [[Gerrit Anne Blaauw|G&nbsp;A&nbsp;Blaauw]], [[Frederick Phillips Brooks, Jr.|F&nbsp;P&nbsp;Brooks&nbsp;Jr]] and [[Werner Buchholz|W&nbsp;Buchholz]] in the ''[[IRE Transactions on Electronic Computers]]'', June 1959, page 121. The notions of that paper were elaborated in Chapter 4 of ''[[#Buchholz-1962|Planning a Computer System (Project Stretch)]]'', edited by W&nbsp;Buchholz, [[McGraw-Hill Book Company]] (1962). The rationale for coining the term was explained there on page 40 as follows:<br/>Byte ''denotes a group of bits used to encode a character, or the number of bits transmitted in parallel to and from input–output units. A term other than ''character'' is used here because a given character may be represented in different applications by more than one code, and different codes may use different numbers of bits (ie, different byte sizes). In input–output transmission the grouping of bits may be completely arbitrary and have no relation to actual characters. (The term is coined from ''[[bite]]'', but respelled to avoid accidental mutation to ''bit''.)''<br/>[[System/360]] took over many of the Stretch concepts, including the basic byte and word sizes, which are powers of 2. For economy, however, the byte size was fixed at the 8-bit maximum, and addressing at the bit level was replaced by byte addressing. [...]}}</ref><ref name="Buchholz_1962">{{anchor|Buchholz-1962}}{{citation |title=Planning a Computer System – Project Stretch |author-first1=Gerrit Anne |author-last1=Blaauw |author-link1=Gerrit Anne Blaauw |author-first2=Frederick Phillips |author-last2=Brooks, Jr. |author-link2=Frederick Phillips Brooks, Jr. |author-first3=Werner |author-last3=Buchholz |author-link3=Werner Buchholz |editor-first=Werner |editor-last=Buchholz |editor-link=Werner Buchholz |publisher=[[McGraw-Hill Book Company, Inc.]] / The Maple Press Company, York, PA. |lccn=61-10466 |year=1962 |chapter=4: Natural Data Units |pages=39–40 |chapter-url=http://archive.computerhistory.org/resources/text/IBM/Stretch/pdfs/Buchholz_102636426.pdf |access-date=2017-04-03 |url-status=dead |archive-url=https://web.archive.org/web/20170403014651/http://archive.computerhistory.org/resources/text/IBM/Stretch/pdfs/Buchholz_102636426.pdf |archive-date=April 3, 2017 |df=mdy-all }}</ref>
* IBM 650 RAMAC (a decimal addressed machine) announcement<ref>{{cite web |title=IBM Archives: 650 RAMAC announcement press release |website=03.ibm.com |date=1956-09-14 |url=http://www-03.ibm.com/ibm/history/exhibits/650/650_pr2.html |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160703085222/http://www-03.ibm.com/ibm/history/exhibits/650/650_pr2.html |archive-date=2016-07-03 |url-status=dead}}</ref>
** "The 650 RAMAC combines the IBM 650 Magnetic Drum Data Processing Machine with a series of disk memory units which are capable of storing a total of 24-million digits. The [[IBM 305 RAMAC|305 RAMAC]] is an entirely new machine which contains its own input and output devices and processing unit as well as a built-in 5-million-digit disk memory."

=== 1957 ===
* The [[IBM 705]] (a decimal addressed machine) Operating manual uses decimal arithmetic for powers of ten, without prefixes.<ref>{{cite web |title=Electronic Date Processing machines: Type 705 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/705/22-6627-4_705_Oper_Jun57.pdf |access-date=2016-06-23}}</ref>
** "A total of {{val|40,000}} characters can be stored within the main storage unit of the Type 705."
** "Each one of the {{val|40,000}} positions in memory is numbered from 0000 to {{val|39,999}}." (page 17)
** "One or more magnetic drums are available as optional equipment with a capacity of {{val|60,000}} characters each."
* Lewis, W. D., Coordinated broadband mobile telephone system<ref>{{cite journal |author-last=Lewis |author-first=W. D. |title=Coordinated broadband mobile telephone system |journal=IRE Transactions on Vehicular Communications |date=June 1957 |volume=9 |pages=43–48 |doi=10.1109/iretvc1.1957.225084 |s2cid=51634558 }}</ref>
** Earliest instance of "kilobit" in both IEEE explore and [[Google Scholar]]: "Central controls the mobile link with a rate of 20 '''kilobits''' per second, or less".

=== 1958 ===
* "64 million (2<sup>26</sup>) bytes" is used in a memo by Dr. [[Werner Buchholz]]<ref>{{cite web |title=Binary Serial Disk File and Error Correction |website=computerhistory.org |url=http://archive.computerhistory.org/resources/text/IBM/Stretch/pdfs/06-16/102632526.pdf}}</ref>

=== 1959 ===
* The term '''32k''' is used in print to refer to a memory size of 32768 (2<sup>15</sup>).
** {{cite book |author-last=Real |author-first=P. |title=Preprints of papers presented at the 14th national meeting of the Association for Computing Machinery on - ACM '59 |chapter=A generalized analysis of variance program utilizing binary logic |pages=78-1–78-5 |date=September 1959 |doi = 10.1145/612201.612294 |publisher=[[ACM Press]] |s2cid=14701651 |quote=On a '''32k core''' size 704 computer, approximately 28,000 datum may be analyzed, ... without resorting to auxiliary tape storage.|doi-access=free }} The author is with the Westinghouse Electric Corporation.

== 1960s ==
=== 1960 ===
* The 11th ''Conférence Générale des Poids et Mesures'' ([[CGPM]]) announces the ''Système International d'Unités'' (SI) and adds the decimal metric prefixes ''[[giga (SI prefix)|giga]]'', and ''[[tera (SI prefix)|tera]]'', defined as 10<sup>9</sup> and 10<sup>12</sup><ref>{{cite web |title=Resolution 12 of the 11th CGPM |publisher=[[BIPM]] |url=http://www.bipm.org/jsp/en/ViewCGPMResolution.jsp?CGPM=11&RES=12 |access-date=2016-06-23}}</ref>
* {{US patent|3,214,691}} Frequency Diversity Communications System is filed on May 13, 1960:
** "In actual construction, the delay line, which provides a total delay from one end to the other of one [[baud]] (10 microseconds for a 100 kilobit per second information rate), may be fabricated from lumped parameter elements, i.e., inductors and capacitors, in a well-known manner."
** "At a 100 kilobit per second information rate, both mark and space signals will generally be transmitted in any 0.0001 sec, interval, and therefore this requirement is easily met with conventional resistors and capacitors."
* {{cite journal |author-last1=Gruenberger |author-first1=Fred |author-last2=Burgess |author-first2=C. R. |title=Letters to the Editor |journal=[[Communications of the ACM]] |volume=3 |issue=10 |date=October 1960 |doi=10.1145/367415.367419|s2cid=3199685 }}
** The '''8K''' core stores were getting fairly common in this country in 1954. The '''32K''' store started mass production in 1956; it is the standard now for large machines and at least 200 machines of the size (or its equivalent in the character addressable machines) are in existence today (and at least 100 were in existence in mid-1959).<ref>The symbol K used in 8K and 32K could have meant 1000 or 1024.</ref>

=== 1955–1961 ===
* A search of the Computer History Museum's Stretch collection<ref>{{cite web |title=IBM Project Stretch |url=http://archive.computerhistory.org/stretch/ |website=[[Computer History Museum]] |access-date=2008-02-25 |url-status=dead |archive-url=https://web.archive.org/web/20080205023039/http://archive.computerhistory.org/stretch/ |archive-date=2008-02-05}}</ref> of 931 text documents dated from September 1955 through September 1961 shows no usage of 'k' or 'K' to describe main storage size.

=== 1961 ===
* {{cite book |author-last=Gray |author-first=L. |author-first2=R. |author-last2=Graham |title=Radio Transmitters |url=http://www.danglaeserbooks.com/si/1286.html |year=1961 |publisher=[[McGraw-Hill]] |location=New York, USA |isbn=978-0-07-024240-1 |quote=In the case of the transmission of business-machine or telemetered data, it is more usual to express the speed in bits or '''kilobits ({{val|1,000}} bits)''' per second.}}
** Quoted in OED as first instance of "{{blue|kilo}}bit", though "it is more usual" suggests it is already in common use (see timeline entry for 1957)
* Described device contains 512 words, 24 bits each (=&nbsp;{{val|12,288}} bits)<ref>{{cite conference |author-first=W., Jr. |last=Gaunt |author-last2=Weller |author-first2=D. |date=1961-02-17 |title=A 12-Kilobit, 5-Microsecond Twistor Variable Store |book-title=1961 IEEE International Solid-State Circuits Conference. Digest of Technical Papers |volume=IV |publisher=[[IEEE]] |location=Philadelphia, PA, USA |pages=106–107 |doi=10.1109/ISSCC.1961.1157351 |url=http://www.paritycomputing.com/jpdfs/ieee/ssc/ireissc4/1961004/01feb/0106gaun.pdf |access-date=2007-03-22}}{{dead link|date=January 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>
* "It is no longer reasonable to spend as much time to transmit an 80-bit address as 12&nbsp;{{blue|kilo}}bits of message information – a 1500 to 1 ratio&nbsp;... We have theoretically and experimentally proved that speech can be compressed from the straightforward requirement for 48&nbsp;{{blue|kilo}}bit PCM channel capability to 2400&nbsp;bits by the application of the Dudley syllabic vocoder."<ref>{{cite journal |author-first=J. |author-last=Halina |date=September 1961 |title=The Telephone Channel in a Global Communications System |journal=IRE Transactions on Communications Systems |volume=9 |issue=3 |publisher=[[IEEE]] |pages=247–252 |issn=0096-2244|doi=10.1109/TCOM.1961.1097700 }}</ref>
* The [[IBM 7090]] Data Processing System (a binary machine), Additional Core Storage (65{{blue|K}} means 'approximately 65000')<ref>{{cite web |title=IBM 7090 Data Processing System, Additional Core Storage – RPQ E02120 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/7090/L22-6636_RPO_E02120_AdditonalCoreStorage_Oct61.pdf |access-date=2016-06-23}}</ref>
** "The Additional Core Storage feature for the IBM 7090 Data Processing System provides a second IBM 7302 Core Storage, increasing the capacity of main storage by {{val|32,768}} words. The block of storage represented by both 7302 units is referred to as "main storage unit".
** "Additional core storage provides two methods of using main storage: (1) The '''65{{blue|K}} mode''' – the computer program is enabled to address both of the main storage units, and (2) the '''32{{blue|K}} mode'''—the computer program is able to address only one storage unit, so that main storage capacity available to that program is effectively 32,768 words."
* The [[IBM 1410]] Data Processing System, which used modified decimal addressing, uses decimal arithmetic for powers of ten, without prefixes<ref>{{cite web |title=IBM Customer Engineering Manual of Instruction - 1410 Data Processing System |url=http://www.bitsavers.org/pdf/ibm/1410/1410_CE_Manual_Oct61.pdf |publisher=IBM |access-date=2020-05-15}}</ref>
** "Core storage units are available in {{val|10,000}}-, {{val|20,000}}- or {{val|40,000}}-character position capacities."
** "The matrix switch makes it possible to address any one of the 100 X-drive lines (in a 10{{blue|K}} core array)."
** "The 40{{blue|K}} core array requires {{val|40,000}} valid five-position addresses from {{val|0,000}} to {{val|39,999}}."
** "This operation check detects errors in programming that cause invalid addresses. Examples: {{val|40,000}}-and-above on a 40{{blue|K}} core array; {{val|20,000}}-and-above on a 20{{blue|K}} core array. On a 10{{blue|K}} core array, invalid addresses are detected by the address-bus validity check."

=== 1962 ===
* A reference to a "4{{blue|k}} IBM 1401" meant {{val|4,000}} characters of storage (memory).<ref>{{cite journal |author-last=Sonquiest |author-first=John A. |title=Fixed-word-length arrays in variable-word-length computers |journal=[[Communications of the ACM]] |volume=5 |issue=12 |page=602 |publisher=[[ACM Press]] |date=December 1962 |doi=10.1145/355580.369093 |s2cid=6781648 |quote=The following scheme for assigning storage for fixed-word-length arrays seems to meet these criteria and has been used successfully in working with linear arrays on a 4k IBM 1401.|doi-access=free }}</ref>

=== 1963 ===
* Ludwig uses {{blue|kilo}}bit in the decimal sense<ref>{{cite journal |author-last=Ludwig |author-first=G. H. |date=August 1963 |title=The Orbiting Geophysical Observatories |journal=Space Science Reviews |volume=2 |issue=2 |pages=175–218 |doi=10.1007/BF00216779 |bibcode=1963SSRv....2..175L |quote=The data handling bit rates can be set by ground command at 1000, 8000, or 64 000 bits per second for the EGO missions, or at 4000, 16 000, or 64 000 bits per second for the POGO missions. ... depending on whether the 1, 4, 8, 16, or 64 kilobit rate is in use.|hdl=2060/19640005640 |s2cid=121835054 |hdl-access=free }}</ref>
* [[Digital Equipment Corporation|DEC]] Serial Drum Type 24<ref>{{cite web|url=http://bitsavers.org/pdf/dec/drum/F-15(24)_serialDrum_Aug63.pdf|title=Serial Drum Type 24|date=1963|publisher=[[Digital Equipment Corporation]]|access-date=2020-05-15}}</ref>
** "Drums are equipped to store either 64, 128, or 256 data blocks, providing a memory capability of 16384, 32768, or 65536 computer words" (no abbreviations)
* [[Honeywell]] 200 Summary Description<ref>{{cite web |title=Honeywell 200 Summary Description |url=http://bitsavers.org/pdf/honeywell/series200/model_200/H200Summary.pdf |date=February 1964 |publisher=[[Honeywell]] |access-date=2020-05-15}}</ref>
** "The main memory is a magnetic core ... The memory unit supplied as part of the basic central processor has a capacity of {{val|2,048}} characters, each of which is stored in a separate, addressable, memory location. This capacity may be expanded in modular increments by adding one {{val|2,048}}-character module and additional 4,096-character modules."
** "Random access disc file and control (disc capacities of up to 100 million characters are available.)"
** "Up to eight drum storage units can be connected to the Model 270 Random Access Drum Control. Each drum provides storage for {{val|2,621,441}} characters, allowing a total capacity of approximately 21 million characters."

=== 1964 ===
* [[Gene Amdahl|Gene Amdahl's]] seminal April 1964 article on [[IBM System/360]] used 1{{brown|K}} to mean 1024.<ref name="IBM360">{{cite journal |author-last1=Amdahl |author-first1=Gene M. |author-link=Gene Amdahl |author-first2=Gerrit |author-last2=Blaauw |author-link2=Gerrit Blaauw |author-first3=Fred |author-last3=Brooks |author-link3=Fred Brooks |title=Architecture of the IBM System/360 |journal=[[IBM Journal of Research and Development]] |volume=8 |issue=2 |pages=87–101 |publisher=[[IBM]] |date=April 1964 |doi=10.1147/rd.82.0087 |url=http://www.research.ibm.com/journal/rd/441/amdahl.pdf}} (NB. Figure 1 gives storage (memory) capacity ranges of the various models in "Capacity 8-bit bytes, 1&nbsp;{{brown|K}} = 1024")</ref>
* Leng, [[Gordon Bell]], et al., use {{brown|K}} in the binary sense: "The computer has two blocks of 4{{brown|K}}, 18-bit words of memory, ('''1{{brown|K}}&nbsp;=&nbsp;1024 words'''), attached to its central processor"<ref>{{cite book |chapter-url=http://research.microsoft.com/users/GBell/Digital/Pulse%20Height%20Analyzer%20Leng%20and%20bellc.pdf |author1=J. Leng |author2=J. A. Quarrington |author3=P. K. Patwardham |author4=C. G. Bell |author4-link=Gordon Bell |chapter=A Time-Shared Computer for Real-Time Information Processing |title=Instrumentation Techniques in Nuclear Pulse Analysis |publisher=National Academy of Sciences-National Research Council |location=Washington, D. C. |id=Publication 1184, Report #40 |date=1964 |archive-url=https://web.archive.org/web/20030309121822/http://research.microsoft.com/users/GBell/Digital/Pulse%20Height%20Analyzer%20Leng%20and%20bellc.pdf |archive-date=2003-03-09 |url-status=dead}}</ref>
* {{cite journal |author-last1=Falkin |author-first1=Joel |author-last2=Savastano |author-first2=Sal |date=May 1963 |title=Sorting with large volume, random access, drum storage |journal=[[Communications of the ACM]] |volume=6 |issue=5 |pages=240–244 |doi=10.1145/366552.366580 |s2cid=11220089 |quote=The Teleregister Telefile data processor includes drum storage whose capacity is far in excess of the requirements for sorting. ... The Telefile data processor provides 16,000 positions in memory, each position storing one binary coded decimal character. A floating accumulator arrangement allows the accumulator to contain any field in memory from 1 to 100 characters in length. All indexing is accomplished programmatically. Input and output tape blocking is fixed at 300 characters per block.|doi-access=free }}
* Data Processing Division press release distributed on April 7, 1964.<ref>{{cite web |title=IBM Archives: System/360 Announcement |website=03.ibm.com |date=1964-04-07 |url=http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PR360.html |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160703073350/http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PR360.html |archive-date=2016-07-03 |url-status=dead}}</ref>
** "System/360 core storage memory capacity ranges from {{val|8,000}} characters of information to more than {{val|8,000,000}}."
* IBM 7090/7094 Support Package for IBM System/360<ref>{{cite web |title=IBM 7090/7094 Support Package for IBM System/360 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/7090/C28-6501-2_7090_SupportForSys360_Nov64.pdf |access-date=2016-06-23}}</ref> – November
** "An IBM 1401 Data Processing System with the following minimum configuration is also required: 1. 4K positions of core storage" {{US patent|3,317,902}} – ADDRESS SELECTION CONTROL APPARATUS – Filed April 6, 1964
** "To facilitate understanding of the invention, the main storage area has been illustrated as being of 8K capacity; however, it is to be understood that the main storage area may be of larger capacity (e.g., 16K, 32K or 64K) by storing address selection control data in bit positions '2', '1' and '0' of M register 197, respectively."

=== 1965 ===
* "Each IBM 2315 disk cartridge can hold the equivalent of more than one million characters of information.<ref>{{cite web |title=IBM 1130 Press Release |website=Ibm1130.net |date=1965-02-11 |url=http://www.ibm1130.net/1130Release.html |access-date=2016-06-23}}</ref>
* "One method of designing a slave memory for instructions is as follows. Suppose that the main memory has 64{{brown|K}} words (where '''{{brown|K}}&nbsp;=&nbsp;1024''') and, therefore, 16 address bits, and that the slave memory has 32 words and, therefore, 5 address bits."<ref>{{cite journal |author-last=Wilkes |author-first=M. V. |title=Slave Memories and Dynamic Storage Allocation |journal=IEEE Transactions on Electronic Computers |volume=EC-14 |issue=2 |pages=270–271 |date=April 1965 |doi=10.1109/PGEC.1965.264263 |quote=One method of designing a slave memory for instructions is as follows. Suppose that the main memory has 64K words (where '''{{brown|K}} = 1024''') and, therefore, 16 address bits, and that the slave memory has 32 words and, therefore, 5 address bits.}}</ref>
* [[IBM 1620]] CPU Model 1 (a decimal machine) System Reference Library, dated 19 July 1965, states:
** "A core storage module, which is {{val|20,000}} addressable positions of magnetic core storage, is located in the 1620. Two additional modules are available ... Each core storage module ({{val|20,000}} positions) is made up of 12 core planes as shown in Figure 3. Each core plane contains all cores for a specific bit value."

=== 1966 ===
* {{US patent|3,435,420}} CONTIGUOUS BULK STORAGE ADDRESSING is filed on 3 January 1966
** "Note that '{{blue|K}}' as used herein indicates 'thousands'. Each storage location in the present embodiment includes 64 data bits and 8 related parity bits, as described herein."
** "Thus, if only storage unit 1A were provided, it would contain addresses 0 through 32K; storage IB would include addresses between 32K and 64K, storage 2A would contain addresses between 64K and 96K,&nbsp;...".

=== 1968 ===
* A Univac 9400 disc based computer system ..." can have 2–8 8411 drives for 14.5–58 {{blue|mega}}bytes capacity. The 8411 has a transfer rate of 156K bytes per second." - using megabytes in a decimal sense<ref>{{cite magazine
 |url=http://bitsavers.org/magazines/Datamation/196802.pdf
 |title=gp computer |date=February 1968  |magazine=[[Datamation]] |volume=14 |issue=2 |page=99 |access-date=July 7, 2024}}</ref>
* Donald Morrison proposes to use the Greek letter kappa ("{{brown|κ}}") to denote {{val|1024}} bytes, "{{brown|κ<sup>2</sup>}}" to denote 1024&nbsp;×&nbsp;1024, and so on.<ref
name="Morrison">{{Cite journal |title= Letters to the editor: Abbreviations for computer and memory sizes
|first= Donald R. |last= Morrison |journal= [[Communications of the ACM]] |volume=11 |issue=3 |date= March 1968 |page=150 |doi= 10.1145/362929.362962|s2cid= 22934466 |doi-access= free }}</ref> (At the time, memory size was small, and only 'K' was in widespread use.)
* [[Wallace Givens]] responded with a proposal to use "{{brown|bK}}" as an abbreviation for 1024 and "{{brown|bK2}}" or "{{brown|bK<sup>2</sup>}}" for 1024&nbsp;×&nbsp;1024, though he noted that neither the Greek letter nor lowercase letter "b" would be easy to reproduce on computer printers of the day.<ref name="Givens">{{Cite journal |title= Letters to the editor: proposed abbreviation for 1024: bK |first=Wallace |last=Givens |journal=[[Communications of the ACM]] |volume=11 |issue=6 |date= June 1968 |page=391 |doi=10.1145/363347.363351|s2cid=22205692 |doi-access=free }}</ref>
* [[Bruce Alan Martin]] of [[Brookhaven National Laboratory]] further proposed that the prefixes be abandoned altogether, and the letter B be used to indicate a base-2 exponent in [[binary scientific notation]], similar to [[E notation|E]] in [[decimal scientific notation]], to create shorthands like 3B20 for 3&nbsp;×&nbsp;2<sup>20</sup><ref name="Martin_1968">{{cite journal |title= Letters to the editor: On binary notation |first=Bruce Alan |last=Martin |journal=[[Communications of the ACM]] |volume=11 |issue=10 |date= October 1968 |page=658 |doi= 10.1145/364096.364107|s2cid=28248410 |doi-access=free }}</ref>

=== 1969 ===
* [[IBM 1401]] (a decimal machine) Simulator for IBM [[OS/360]]<ref>{{cite web |title= 1401 Simulator For OS/360 |url= http://www.bitsavers.org/pdf/ibm/360/1401_emulator/360D-11.1.019_1401simCorr_Sep69.pdf |access-date= 2020-05-15}}</ref>
** "1401 features supported are advanced programming, sense switches, tapes, multiply, divide, 16K core, and all standard instructions except Select Stacker."
** "1401 core is simulated by {{val|16,000}} bytes of S/360 core obtained dynamically."
** "Enough core must be available to allow at least 70K for a problem program area. If tape simulation is not required, this core requirement may be reduced to 50K with the removal of the tape Buffer area."
* {{US patent|3,638,185}} HIGH DENSITY PERMANENT DATA STORAGE AND RETRIEVAL SYSTEM is filed on March 17, 1969, earliest Google Patent search containing "kilobyte".
** "The data word processor 606 handles the inflow and out-flow of byte-oriented input/output data and interleaved signals at a rate of, for example, 500 kilobytes per second. Instruction processing rates of four to eight per microsecond are required for such a data flow."
* {{US patent|3,618,041}} Memory Control System is filed on October 29, 1969
** "FIG. 2a shows a practical example of an operand address which consists of, for example 24 bits. It is assumed herein that each block includes 32 bytes, each sector includes 1 kilobyte, the buffer memory 116 includes 4 kilobytes, and read data is represented by one double word or 64 bits, as one word in this case consists of 32 bits."
* IBM System/360 Component Descriptions<ref>{{cite web |title=IBM System/360 Component Descriptions – 2314 Direct Access Storage Facility and 2844 Auxiliary Storage Control |url= http://bitsavers.org/pdf/ibm/dasd/2314/A26-3599-4_2314_2844_Component_Description_Sep69.pdf |date=September 1969 |id=A26-3599-4 |publisher=IBM |access-date=2024-07-06}}</ref> (IBM 2314 Direct Access Storage Facility)
** "Each module can store 29.17 million bytes or 58.35 million packed decimal digits ... total on-line storage capacity is 233.4 million bytes"
* "Each 11-disc pack (20 surfaces) has a storage capacity of 29 megabytes; maximum storage capacity with the largest version using a ninth drive as a spare) is {{val|233,400,000}} bytes."<ref>{{cite magazine |url=http://bitsavers.org/magazines/Datamation/196909.pdf |title=multi-disc drive |magazine=[[Datamation]] |volume=15 |issue=9 |page=206 |date=September 1969 |access-date=July 7, 2024}}</ref>
* [[Digital Equipment Corporation|DEC]] [[PDP-11]] (a binary-addressed machine) Handbook<ref>{{cite web |title=PDP11 Handbook |website= Research.microsoft.com |url= http://research.microsoft.com/~GBell/Digital/PDP%2011%20Handbook%201969.pdf |access-date= 2016-06-23}}</ref>
** "PDP-11 addressing modes include ... and direct addressing to 32K words" (Page 2)  This appears to be the only use of 'K' in this manual, though; elsewhere sizes are spelled out in full. Contrast the 1973 PDP-11/40 Manual, which defines 'K' as {{val|1024}} (below).
* "...&nbsp;each removable disc has a capacity of 2.3 million bytes or 3.07 million 6-bit characters. Up to four drives can be attached to a single controller, resulting in a total storage capacity of 9.2 {{blue|mega}}bytes." Usage of "million" and "{{blue|mega-}}" in decimal sense to describe HDD.<ref>{{cite magazine |url=http://bitsavers.org/magazines/Datamation/196912.pdf |title=inexpensive discs |magazine=[[Datamation]] |volume=15 |issue=12 |page=247 |date=December 1969 |access-date=July 7, 2024}}</ref>

== 1970s ==
=== 1970 ===
* "The following are excerpts from an IBM Data Processing Division press technical fact sheet distributed on 30 June 1970.
** Users of the Model 165 will have a choice of five main core storage sizes, ranging from {{val|512,000}} to over 3-million bytes. Seven main memory sizes are available for the Model 155, ranging from {{val|256,000}} to over 2-million bytes."<ref>{{cite web |title=IBM Archives: System/370 Model 155 (continued) |website=03.ibm.com |date=1970-06-30 |url=http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3155B.html |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160703034550/http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3155B.html |archive-date=2016-07-03 |url-status=dead}}</ref>
* {{cite journal |author-last1=Weiler |author-first1=Paul W. |author-first2=Richard S. |author-last2=Kopp |author-first3=Richard G. |author-last3=Dorman |title=A Real-Time Operating System for Manned Spaceflight |journal=[[IEEE Transactions on Computers]] |volume=19 |issue=5 |pages=388–398 |date=May 1970 |issn=0018-9340 |doi=10.1109/T-C.1970.222936|s2cid=38803844 }} "Each of the five system/360 model 75 computers (Fig. 2) has one megabyte of primary core storage plus four megabytes of large core storage (LCS, IBM 2361)."

=== 1971 ===
* IBM System/360 Operating System: Storage Estimates<ref>{{cite web |title=IBM System/3S0 Operating System: Storage Estimates |edition=Twelfth |date=January 1971 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/ibm/360/os/R20.0_Jan71/GC28-6551-12_OS_StorageEstimates_R20_Jan71.pdf |access-date=2016-06-23}}</ref> uses K in a binary sense approximately 450 times, such as "System/360 Configuration: Model 40 with 64K bytes of storage and storage protection". Note the letter "K" is also sometimes used as a variable in this document (see page 23).

=== 1972 ===
* Lin and Mattson introduce the term '''Mbyte'''.
** {{cite journal |author-last1=Lin |author-first1=Yeong |author-last2=Mattson |author-first2=Richard|author2-link=Richard Mattson |title=Cost-performance evaluation of memory hierarchies |journal=[[IEEE Transactions on Magnetics]] |volume=8 |issue=3 |pages=390–392 |publisher=[[IEEE]] |date=September 1972 |doi=10.1109/TMAG.1972.1067329 |bibcode=1972ITM.....8..390L |quote=Also, random access devices are advantageous over serial access devices for backing store applications only when the memory capacity is less than '''1 Mbyte'''. For capacities of '''4 Mbyte''' and '''16 Mbyte''' serial access stores with shift register lengths of 256-bit and 1024-bit, respectively, look favorable.}}

=== 1973 ===
* {{cite journal |author-last=Habib |author-first=Stanley |title=Notes from industry |journal=ACM SIGMICRO Newsletter |volume=4 |issue=3 |page=29 |publisher=[[ACM Press]] |date=October 1973 |doi=10.1145/1217132.1217137|s2cid=8712609 }}<ref>{{cite journal |title=Notes from industry |doi=10.1145/1217132.1217137 |journal=ACM SIGMICRO Newsletter |volume=4 |issue=3 |pages=29 |year=1973 |last1=Habib |first1=Stanley |s2cid=8712609 }}</ref>
** OCEANPORT, N.J., SEPT. 25, 1973 – A 16-bit minicomputer priced at under $2,000.00 in quantities and a 32-bit minicomputer priced at under $6,000.00 in quantities were introduced today by Interdata, Inc. The 16-bit mini, the Model 7/16, includes an '''8KB''' memory unit in its basic configuration, and will be available for delivery in the first quarter of 1974. The single unit price of the 7/16 is $3,200.00. The 32-bit mini, the Model 7/32, includes a '''32KB''' memory unit and will be available for delivery in the second quarter of 1974. The single unit price of the 7/32 is $9,950.00.
* [[Digital Equipment Corporation|DEC]] PDP-11/40 Manual<ref>{{cite web |title=PDP11-40 Manual: Page 9/212 |website=Pdos.csail.mit.edu |url=http://pdos.csail.mit.edu/6.828/2005/pdp11/pdp11-40-000009.html |access-date=2016-06-23}}</ref>
** "Direct addressing of 32{{brown|K}} 16-bit words or 64{{brown|K}} 8-bit bytes ({{brown|K}} = {{val|1024}})" (Page 1-1) Contrast the 1969 PDP-11 Handbook, which avoids this usage almost everywhere (above).

=== 1974 ===
* The seminal 1974 [[IBM 3340|Winchester HDD]] article makes extensive use of '''{{blue|M}}bytes''' with M being used in the conventional, 10<sup>6</sup> sense.<ref>{{cite journal |title=Engineering Design of a Disk Storage Facility with Data Modules |url=http://www.research.ibm.com/journal/rd/186/ibmrd1806D.pdf |journal=[[IBM Journal of Research and Development]] |date=November 1974 |first=R. B. |last=Mulvany |volume=18 |issue=6 |pages=489–505 |doi=10.1147/rd.186.0489 |access-date=2008-02-25 |url-status=dead |archive-url=https://web.archive.org/web/20071202120454/http://www.research.ibm.com/journal/rd/186/ibmrd1806D.pdf |archive-date=2007-12-02}}</ref>  Arguably all of today's HDD's derive from this technology.
* The October 1974 [[Control Data Corporation|CDC]] Product Line Card unambiguously uses '''{{blue|M}}B''' to characterize HDD capacity in millions of bytes.<ref>{{cite web |title=Flexible Disk Drive: Model Number 9400 |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/cdc/discs/brochures/ProductLine_Oct74.pdf |access-date=2016-06-23}}</ref>

=== 1975 ===
* The 15th CGPM defines the [[SI prefix]]es ''{{blue|peta}}'' as 10<sup>15</sup> and ''{{blue|exa}}'' as 10<sup>18</sup>.<ref>{{cite web |title=Resolution 10 of the 15th CGPM |publisher=[[BIPM]] |url=http://www.bipm.org/jsp/en/ViewCGPMResolution.jsp?CGPM=15&RES=10 |access-date=2016-06-23}}</ref>
* [[Byte (magazine)|Byte Magazine]] December 1975 article on IBM 5100 includes the following:
** "User memory starts at 16K bytes in the minimum configuration and can be expanded to 64K bytes (65,536)."
* [[Gordon Bell]] uses the term '''megabytes''':
** {{cite book |author-last1=Bell |author-first1=Gordon |author-last2=Strecker |author-first2=William |title=Proceedings of the 3rd annual symposium on Computer architecture - ISCA '76 |chapter=Computer structures: What have we learned from the PDP-11? |pages=1–14 |publisher=[[ACM Press]] |date=November 1975 |doi=10.1145/800110.803541 |s2cid=14496112 |chapter-url=http://research.microsoft.com/~gbell/Digital/Bell_Strecker_What_we%20_learned_fm_PDP-11c%207511.pdf |quote=memory size (8k bytes to 4 '''megabytes''').}}<ref>{{cite journal |title=Computer structures |doi=10.1145/633617.803541 |journal=ACM SIGARCH Computer Architecture News |volume=4 |issue=4 |pages=1–14 |year=1976 |last1=Bell |first1=Gordon |last2=Strecker |first2=William D. |doi-access=free }}</ref>

=== 1976 ===
* DEC RK05/RK05J/RK05F disk drive maintenance manual<ref>{{cite web|url=http://bitsavers.org/pdf/dec/disc/rk05/EK-RK5JF-MM-001_RKO5_RK05J_RK05F_Disk_Drive_Maintenance_Manual_Nov76.pdf|title=RK05/RK05J/RK05F disk drive maintenance manual|date=1975|id=EK-RK5JF-MM-001|publisher=[[Digital Equipment Corporation]]|access-date=2020-05-15}}</ref>
** "Bit Capacities (unformatted)" "25 million" | "50 million" ({{val|57,600}} bits/track × 406 | 812 tracks = {{val|23,385,600}} | {{val|46,771,200}} bits)
* The Memorex 1976 annual report has 10 instances of the use of megabyte to describe storage devices and media.<ref>{{cite web |title=Welcome to the Information Technology Corporate Histories Collection |website=[[Computer History Museum]] |url=http://www.computerhistory.org/corphist/view.php?s=documents&id=364 |access-date=2016-06-23}}</ref>
* Caleus Model 206-306 Maintenance Manual uses 3'''{{blue|M}}B''' to characterize a drive having {{val|3,060,000}} bytes capacity.<ref>{{cite web |title=Drive Type 100 TPI & 200 TPI: Specifications |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/caelus/Caelus206-306_Maint_1976.pdf |access-date=2016-06-23}}</ref>
* The first 5{{frac|1|4}} inch floppy disk drive, the Shugart SA&nbsp;400, is introduced in August 1976. The drive had 35 tracks and was single sided. The data sheet gives the unformatted capacity as 3125 bytes per track for a total of '''109.4 {{blue|K}}bytes''' ({{val|3125}} × 35 = {{val|109,375}}). When formatted with 256 byte sectors and 10 sectors per track the capacity is '''89.6 {{blue|K}}bytes''' (256 × 10 × 35 = {{val|89,600}}).<ref>{{cite web |title=SA400 minifloppy |website=Swtpc.com |date=2013-08-14 |url=http://www.swtpc.com/mholley/SA400/SA400_Index.htm |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160805062202/http://www.swtpc.com/mholley/SA400/SA400_Index.htm |archive-date=2016-08-05 |url-status=usurped}}</ref>

=== 1977 ===
* HP 7905A Disc Drive Operator's Manual<ref>{{cite web|url=http://bitsavers.org/pdf/hp/disc/7905_7906/07905-90009_7905A_OP_Mar77.pdf|title=HP 7905A Disc Drive Operator's Manual|publisher=[[Hewlett-Packard]]|id=07905-90009|date=March 1977}}</ref>
** "nearly 15 million bytes" with no other abbreviations
* 1977 Disk/Trend Report – Rigid Disk Drives, published June 1977
** This first edition of the annual report on the hard disk drive industry makes extensive use of '''{{blue|M}}B''' as 10<sup>6</sup> bytes. The industry, in 1977, is segmented into nine segments ranging from "Disk Cartridge Drives, up to 12&nbsp;{{blue|M}}B" to "Fixed Disk Drives, over 200&nbsp;{{blue|M}}B."  While the categories changed during the next 22 years of publication, Disk/Trend, the principal marketing study of the hard disk drive industry always and consistently categorized the industry in segments using prefixes '''{{blue|M}}''' and later '''{{blue|G}}''' in the decimal sense.
* VAX-11/780 Architecture Handbook 1977–78. Copyright 1977 Digital Equipment Corporation.
** Page 2-1 "physical address space of 1 '''gigabyte''' (30 bits of address)" The initial hardware was limited to '''2 M bytes''' of memory utilizing the '''4K''' MOS RAM chips. The VAX11/780 handbooks use '''M byte''' and '''Mbyte''' in the same paragraph.<ref>{{cite web |title=VAX-11/780 Architecture Handbook |url=http://bitsavers.org/pdf/dec/vax/handbook/VAX_Architecture_Handbook_Vol1_1977.pdf |publisher=[[Digital Equipment Corporation]] |date=1977 |access-date=2020-05-15}}</ref>

=== 1978 ===
* [[Digital Equipment Corporation|DEC]] RM02/03 Adapter Technical Description Manual<ref>{{cite web|url=http://bitsavers.org/pdf/dec/disc/rm03/EK-RM023-TD-001_RM02_03_Tech_May78.pdf|title=RM02/03 Adapter Technical Description Manual|publisher=[[Digital Equipment Corporation]]|date=May 1978|id=EK- RM023-TO-001|access-date=2020-05-15}}</ref>
** "The RM02 or RM03 Disk Drive (Figure 1-1) is an 80{{blue|M}} byte (unformatted; 67{{blue|M}} byte formatted) ... storage device ... in the 16-bit format, the maximum storage capacity is {{val|33,710,080}} data words per disk pack" ({{val|33,710,080}} × 16 / 8 = {{val|67,420,160}} 8-bit bytes)

=== 1979 ===
* [[Fujitsu]] M228X Manual<ref>{{cite web|url=http://bitsavers.org/pdf/fujitsu/disk/M228X/B03P-4580-0100A_M228x_Apr81.pdf|title=Fujitsu M228X Manual}}</ref>
** "Storage capacity (unformatted)" "67.4&nbsp;{{blue|M}}B", "84.2&nbsp;{{blue|M}}B", etc.
** "{{val|20,480}} Bytes" per track, 4 tracks per cylinder, 808+15 cylinders = {{val|67,420,160}} bytes
* [[Sperry Corporation|Sperry]] [[UNIVAC|Univac]] Series V77 Microcomputer Systems Brochure, Circa 1978, Printed July 1979<ref>{{cite web |title=Sperry Univac Series V77 Minicomputer Systems: Power, Performance, Productivity, 1978 |website=Archive.computerhistory.org |url=http://archive.computerhistory.org/resources/text/Remington_Rand/SperryUnivac.V77.1978.102646156.pdf |access-date=2016-06-23}}</ref>
** Page 5: Table list memory options as '''64KB, 128KB, and 256KB'''. Memory Expansion is up to '''2048KB'''
** Page 9: "Memory for the V77-800 is available in '''128K byte''' and '''256K byte''' increments up to a maximum of '''2&nbsp;megabytes'''"
** Page 21: Moving Head Disks – units up to '''232 million byte''' disk pack systems. Diskette – storage of '''0.5&nbsp;MB''' per drive.

== 1980s ==
=== 1980 ===
* [[Shugart Associates]] Product Brochure, published June 1980 specifies the capacity of its two HDDs using megabytes and MB in a decimal sense, e.g. SA1000 formatted capacity is stated as "8.4&nbsp;{{blue|M}}B" and is 256&nbsp;×&nbsp;32&nbsp;×&nbsp;1024&nbsp;= {{val|8,388,608}} bytes.
* Shugart Associates SA410/460 Data Sheet published October 1980 contains capacity specifications as follows: 
{| class="wikitable"
|-
! Formatted Capacity
! SA410<br />Single/Double Density
! SA460<br />Single/Double Density
|-
| Per Disk
| 204.8/409.6 KBytes
| 409.6/819.2 KBytes
|-
| Per Surface
| 204.8/409.6 KBytes
| 204.8/409.6 KBytes
|-
| Per Track
| 2.56/5.12 KBytes
| 2.56/5.12 KBytes
|-
| Sectors/Track
| 10
| 10
|} The same data sheet uses MByte in a decimal sense.

=== 1981 ===
* [[Intel 8086|8086]] Object Module Formats<ref>{{cite web |title=8086 Relocatable Object Module Formats |url=http://www.bitsavers.org/pdf/intel/ISIS_II/121748-001_8086_Relocatable_Object_Module_Formats_Nov81.pdf |page=5 |publisher=[[Intel]] |date=1981 |id=121748-001 |access-date=2020-05-15}}</ref>
** "The 8086 MAS is 1 {{brown|mega}}byte ({{val|1,048,576}})"
* [[Quantum Corp.|Quantum]] Q2000 8" Media Fixed Disk Drive Service Manual<ref>{{cite web |title=Quantum Service Manual: Q2000 8" Media Fixed Disk Drive |publisher=[[Quantum Corp.|Quantum]] |url=http://www.bitsavers.org/pdf/quantum/Q2000/81-40238A_Q2000_svc_Sep81.pdf |access-date=2020-05-15}}</ref>
** "four models ... the Q2010 having an unformatted 10.66&nbsp;Mb capacity on one disk platter and two heads, the ... 21.33&nbsp;Mb ... 32.00&nbsp;Mb ... 42.66&nbsp;Mb"
** (1024 tracks&nbsp;× "10.40Kb" per track = 10649&nbsp;"Kb", which they write as "10.66Mb", so 1&nbsp;"Mb" = 1000&nbsp;"Kb")
** (256 Bytes per sector, 32 Sectors/tk = 8192 bytes, which they write as "8.20Kb" per track)
** "Storage capacity of 10, 20, 30, or 40 megabytes"
** 4.34M bits/second transfer rate"
* [[Apple Disk III]] data sheet<ref>{{cite web |url=http://www.macmothership.com/gallery/MiscAds/diskIIIa.gif |format=GIF |title=Apple Disk: Accessories |website=Macmothership.com |access-date=2016-06-23}}</ref><ref>{{cite web |title=Apple Disk III |website=Macmothership.com |format=GIF |url=http://www.macmothership.com/gallery/MiscAds/diskIIIb.gif |access-date=2016-06-23}}</ref>
** "Formatted Data Capacity: 140K bytes"
** Apple uses K in a binary sense since the actual formatted capacity is 35 tracks&nbsp;× 16 sectors/track&nbsp;× 256 bytes/sector&nbsp;= 140&nbsp;KiB&nbsp;= 143.360&nbsp;kB

=== 1982 ===
* Brochure for the [[IBM Personal Computer]] (PC)<ref>{{cite web |title=Check us out |format=JPG |website=Digitalize.textfiles.com |url=http://digitize.textfiles.com/items/1982-ibm-personal-computer/.m/1982-IBM-Personal-Computer-04.jpg |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20220530080703/http://digitize.textfiles.com/items/1982-ibm-personal-computer/.m/1982-IBM-Personal-Computer-04.jpg |archive-date=2022-05-30}}</ref>
** "User memory: 16KB to more than 512KB", "single-sided '''160KB''' or double-sided '''320KB''' diskette drives"
* IBM ''Technical Reference: Personal Computer Hardware Reference Library''<ref>{{cite book |author=IBM |author-link=IBM |title=Technical Reference: Personal Computer Hardware Reference Library |publisher=[[IBM Corp.]] |date=July 1982 |edition=Revised |pages=2–93 |id=6025008}}</ref>
** "The drives are soft sectored, single or double sided, with 40 tracks per side. They are Modified Frequency Modulation (MFM) coded in 512 byte sectors, giving a formatted capacity of '''{{val|163,840}} bytes''' per drive for single sided and '''{{val|327,680}} bytes''' per drive for double sided."
* [[Seagate Technology|Seagate]] ST&nbsp;506/412 OEM Manual<ref>{{cite book |title=ST 506/412 OEM Manual |publisher=[[Seagate Technology]] |url=http://www.bitsavers.org/pdf/seagate/mfm/ST-412/ST412_OEMmanual_Apr82.pdf |access-date=2022-06-30}}</ref>
** "Total formatted capacity [...] is 5/10 megabytes (32 sectors per track, 256 bytes per sector, 612/1224 tracks)"

=== 1983 ===
* [[IBM]] [[IBM System/360|S/360]] [[IBM System/370|S/370]] Principles Of Operation GA22-7000 includes as statement:
** "In this publication, the letters {{brown|K}}, {{brown|M}} and {{brown|G}} denote the multipliers 2<sup>10</sup>, 2<sup>20</sup> and 2<sup>30</sup> respectively. Although the letters are borrowed from the decimal system and stand for {{blue|kilo}} 10<sup>3</sup>, {{blue|mega}} 10<sup>6</sup> and {{blue|giga}} 10<sup>9</sup> they do not have decimal meaning but instead present the power of 2 closest to the corresponding power of 10."
* IBM 341 4-inch Diskette Drive<ref>{{cite web |url=http://bitsavers.org/pdf/ibm/floppy/DemiDiskette/IBM341_4inch_DemiDiskette_Mar83.pdf |title=IBM 341 Four-Inch Diskette Drive Description and Maintenance Information |publisher=[[IBM]] |date=March 1983 |access-date=2020-05-15}}</ref>
** unformatted capacity "{{val|358,087}} bytes"
** "Total unformatted capacity (in kilobytes): 358.0"
* [[Maxtor]] XT-1000 brochure<ref>{{cite web |title=The Maxtor XT-1000 Family: Fixed Disk Drives |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/maxtor/mfm/XT1000-XT3000_brochures.pdf |access-date=2016-06-23}}</ref>
** "Capacity, unformatted" 9.57&nbsp;MB per surface = 10,416 bytes per track × 918 tracks per surface = 9,561,888 byte (decimal MB)
* [[Shugart Associates]] SA300/350 Data Sheet published c. November 1983 (one of the first MIC standard 3.5" FDDs) contains capacity specifications as follows: 
{| class="wikitable"
|-
! Formatted Capacity
! Single Sided<br />Single/Double Density
! Double Sided<br />Single/Double Density
|-
| Per Disk
| 204.8/409.6 kbytes
| 409.6/819.2 kbytes
|-
| Per Surface
| 204.8/409.6 kbytes
| 204.8/409.6 kbytes
|-
| Per Track
| 2.56/5.12 kbytes
| 2.56/5.12 kbytes
|-
| Sectors/Track
| 10
| 10
|} Shugart Associates, one of the leading FD companies used k in a decimal sense.

=== 1984 === 
* {{anchor|Mac1984}}'''The [[Classic Mac OS|Macintosh Operating System]] is the earliest known operating system using the prefix K in a binary sense to report both memory size and HDD capacity'''.<ref>{{cite web |author-first=Marcin |author-last=Wichary |title=GUIdebook > Screenshots > System 1.1 |website=Guidebookgallery.org |url=http://www.guidebookgallery.org/screenshots/macos11 |access-date=2016-06-23}}</ref>
** In the original 1984 Apple Macintosh ad, page 8, Apple characterized its 3{{frac|1|2}} floppy disk as "400{{brown|K}}", that is, 800&nbsp;×&nbsp;512 byte sectors or {{val|409,600}} bytes = 400&nbsp;KiB. Similarly, the February 1984 [[Byte (magazine)|Byte Magazine]] review describes the FD as "400{{brown|K}} bytes".<ref>{{cite web |author-last=Williams |author-first=Gregg |title=Attached > Computer history &gt Macintosh preview in Byte |website=Aresluna.org |date=2004-01-20 |url=http://www.aresluna.org/attached/computerhistory/articles/macintoshbytepreview |access-date=2016-06-23}}</ref>
<!-- added to link from Binary Prefix article -->

=== 1985 ===
* [[Exabyte (company)|Exabyte Corp.]] founded
* September 1985. Apple introduced Macintosh Finder 5.0 with HFS (Hierarchical File System)along with the Mac's first hard drive, the Hard Disk 20. Finder 5.x displayed drive capacity in binary K units. The Hard Disk 20 Manual specified the HDD as having
** "Data capacity (formatted): {{val|20,769,280}} bytes
** Bytes per block: 532 (512 user data, 20 system data)
** Total disk blocks: {{val|39,040}}
* and has the following definition in its glossary:<br/><span>''megabyte''<br/>''Approximately one million bytes ({{val|1,048,567}}) of information. A 20 megabyte hard disk holds 20 million bytes of information, or 20,000 kilobytes (20,000K)'' (Apple Hard Disk 20 Manual)</span><br/>The user data is {{val|39,040}} × 512 = {{val|19,988,480}} bytes here.

=== 1986 ===
* [[Apple IIgs]] introduced September 1986
** [[Apple ProDOS|ProDos16]] uses MB in a binary sense.
** Similar usage in "ProDOS Technical Reference Manual" (c) 1985, p.&nbsp;5 & p.&nbsp;163
* Digital Large System Mass Storage Handbook (c) dated September 1986
** "GByte: An abbreviation for one billion (one thousand million) bytes." p.&nbsp;442
** "M: An abbreviation for one million. Typically combined with a unit of measure, such as bytes (MBytes), or Hertz (MHz)." p.&nbsp;444

=== 1987 ===
* [[Seagate Technology|Seagate]] Universal Installation Handbook<ref>{{cite web |title=Universal Installation Handbook |website=Bitsavers.org |url=http://www.bitsavers.org/pdf/seagate/Seagate_Universal_Installation_Handbook.pdf |access-date=2016-06-23}}</ref>
** ST125 listed as 21 "Megabytes" formatted capacity, later document<ref>{{cite web |title=ST125 Installation Guide |url=http://www.seagate.com/support/disc/specs/mfm/st125.html |access-date=2008-02-25 |url-status=dead |archive-url=https://web.archive.org/web/20070926234741/http://www.seagate.com/support/disc/specs/mfm/st125.html |archive-date=2007-09-26}}</ref> seems{{original research inline|date=August 2015}} to confirm that this is decimal
* Disk/Trend Report – Rigid Disk Drives, October 1987
** First use of '''GB''' in a decimal sense in this HDD marketing survey; Figure 1 states "FIXED DISK DRIVES more than 1 GB" market size as $10,786.6 million.
* [[Merriam-Webster's Collegiate Dictionary|Webster's Ninth New Collegiate Dictionary]] (1987) has binary definitions for kilobyte and megabyte.
** '''{{brown|kilo}}byte''' ''n'' [from the fact that {{val|1024}} (2<sup>10</sup>) is the power of 2 closest to {{val|1000}}] (1970): {{val|1024}} bytes
** '''{{brown|mega}}byte''' ''n'' (1970): {{val|1,048,576}} bytes

=== 1988 ===
* [[Control Data Corporation|Imprimis]] Wren VII 5{{frac|1|4}} Inch Rigid Disk Drive Data Sheet, printed 11/88
** "Capacity of 1.2 gigabyte (GB)"

=== 1989 ===
* [[IBM]] [[IBM System/370|Enterprise Systems Architecture/370]], Reference Summary (GX20-0406-0), p.&nbsp;50 (the last page), has a two table, one to recap the decimal value of power of 2 and 16 to 2<sup>60</sup>, and one that read:
{| class="wikitable"
|-
! Symbol
! Value
|-
| {{brown|K}}&nbsp;({{brown|kilo}})
| {{val|1,024}}&nbsp;= 2<sup>10</sup>
|-
| {{brown|M}}&nbsp;({{brown|mega}})
| {{val|1,048,576}}&nbsp;= 2<sup>20</sup>
|-
| {{brown|G}}&nbsp;({{brown|giga}})
| {{val|1,073,741,824}}&nbsp;= 2<sup>30</sup>
|}
* Electronic News, 25 September 1989, '''"Market 1.5GB Drives"'''
** "Imprimis and [[Maxtor]] are the only two drive makers to offer the new generation of drives in the 1.5GB capacity range&nbsp;..."
** "IBM, Hewlett-Packard, Fujitsu, Toshiba, Hitachi and Micropolis are expected to enter the market for 1.5GB capacity..."

== 1990s ==
=== 1990 ===
* Matsuda et al.<ref>{{cite journal |title=Integration of 1024 InGaAsP/InP optoelectronic bistable switches |author1=K. Matsuda |author2=K. Takimoto |author3=D.-H. Lee |author4=J. Shibata |journal=IEEE Transactions on Electron Devices |volume=37 |issue=7 |pages=1630–1634 |date=July 1990 |doi=10.1109/16.55749|bibcode=1990ITED...37.1630M }}</ref> refer to {{val|1024}} bits (32&nbsp;×&nbsp;32 optoelectronic switches) as "1-kb memory".
* [[GEOS (8-bit operating system)|GEOS]] ad<ref>{{cite web |title=Advertisement for GEOS |url=http://www.commodore.ca/gallery/adverts_other/512k_compute_april90.jpg |access-date=2008-02-25 |url-status=dead |archive-url=https://web.archive.org/web/20071202120454/http://www.commodore.ca/gallery/adverts_other/512k_compute_april90.jpg |archive-date=2007-12-02}}</ref>
** "512K of memory"
* The enhanced [[DOS]] [[command line processor]] [[4DOS 3.00]] supports a number of additional conditions (DISKFREE, DOSMEM/DOSFREE, EMS, EXTENDED, FILESIZE and XMS) in [[IF (DOS command)|IF]] commands, which allow to test for sizes in bytes, kilobytes (by appending a ''K'') or megabytes (by appending an ''M''), where 1{{brown|K}} is defined as 1024&nbsp;bytes and 1{{brown|M}} is defined as {{nowrap|1024 × 1024}} bytes.<ref name="4DOS_3.00_HELP">{{cite book |title=4DOS.DOC 3.00 |title-link=4DOS 3.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-link2=Tom Rawson |author-first3=Rex C. |author-last3=Conn |author-link3=Rex C. Conn |date=1990-03-07 |version=3.00}}</ref>
* [[Digital Equipment Corporation|DEC]] RA90/RA92 Disk Drive Service Manual<ref>{{cite web |title=RA90/RA92 Disk Drive Service Manual |website=Bitsavers.org |url=http://bitsavers.org/pdf/dec/disc/ra90/EK-ORA90-SV-003_RA90_RA92_Service_Jun90.pdf |access-date=2016-06-23}}</ref>
** "RA90 Disk Drive ... Storage capacity, formatted 1.216&nbsp;{{blue|giga}}bytes" ({{val|512|u=bytes/sector}} × {{val|69|u=sectors/track}} × {{val|34437|u=tracks}} = {{val|1216590336|u=bytes}})

=== 1991 ===
* The 19th CGPM defines the [[SI prefix]]es ''{{blue|zetta}}'', and ''{{blue|yotta}}'' as 10<sup>21</sup> and 10<sup>24</sup>.<ref>{{cite web |title=Resolution 4 of the 19th CGPM |publisher=[[BIPM]] |url=http://www.bipm.org/jsp/en/ViewCGPMResolution.jsp?CGPM=19&RES=4 |access-date=2016-06-23}}</ref>
* May 13: Apple releases Macintosh System 7<ref>{{cite web |title=System 7.0 – Will it be on apple.com? |website=Macgui.com |url=http://macgui.com/usenet/?group=53&id=83125 |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160401212219/http://macgui.com/usenet/?group=53&id=83125 |archive-date=2016-04-01 |url-status=dead}}</ref> containing Finder 7.0, which uses M in a binary sense to describe HDD capacity.<ref>{{cite web |author-first=Marcin |author-last=Wichary |title=GUIdebook > Screenshots > File manager |website=Guidebookgallery.org |url=http://www.guidebookgallery.org/screenshots/filemanager |access-date=2016-06-23}}</ref>
* The [[HP 95LX]] uses "1MB" in a binary sense to describe its RAM capacity.{{citation needed|date=August 2015}}
* [[Micropolis (company)|Micropolis]] 1528 Rigid Disk Drive Product Description<ref>{{cite web|url=http://bitsavers.org/pdf/micropolis/105389b_1528_1991.pdf|title=Micropolis 1528 5 1/4-Inch Full-Height Rigid Disk Drive 1.53 GBytes SCSI Interface Product Description|publisher=[[Micropolis (company)|Micropolis]]|date=1991|id=105389 Rev B}}</ref>
** "1.53 {{blue|G}}Bytes" ... "Up to 1.53 {{blue|giga}}bytes (unformatted) per drive" "{{blue|M}}Bytes/Unit: 1531.1" ({{val|2100}} × {{val|48,608}} × 15 = {{val|1,531,152,000}})
* Similar to a feature in 4DOS 3.00, the enhanced [[command line processor]] [[4DOS&nbsp;4.00]] adds support for a number of [[4DOS variable function|variable function]]s (like <code>%@FILESIZE[''...'']%</code>), taking special arguments to control the format of the returned values: The lowercase letters ''k'' and ''m'' are used as decimal prefixes, whereas the uppercase letters ''K'' and ''M'' are used in their binary meaning.<ref name="4DOS_4.00_HELP">{{cite book |title=4DOS.DOC 4.00 |title-link=4DOS 4.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-link2=Tom Rawson |author-first3=Rex C. |author-last3=Conn |author-link3=Rex C. Conn |date=1991-11-01 |version=4.00}}</ref><ref name="4DOS_8.00_HELP">{{cite book |title=4DOS 8.00 online help |title-link=4DOS 8.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-link2=Tom Rawson |author-first3=Rex C. |author-last3=Conn |author-link3=Rex C. Conn |author-first4=Matthias R. |author-last4=Paul |author-first5=Charles E. |author-last5=Dye |author-first6=Luchezar I. |author-last6=Georgiev |date=2002-02-27}}</ref>
* T. Smith, W. Moorman and T. Dang refer to 2<sup>20</sup> microseconds as a "{{brown|mega}}-{{blue|micro}}second (MUS)", mixing binary use of the prefix "mega-" with the conventional decimal prefix micro.<ref>{{cite conference |last1=Smith |first1=T. B. |last2=Moorman |first2=W. A. |last3=Dang |first3=T |date=January 1991 |title=The IBM S/390 Sysplex Timer |doi=10.1109/FTCS.1991.146653 |book-title=Digest of Papers. Fault-Tolerant Computing: The Twenty-First International Symposium |pages=144–145 |publisher=[[IEEE Computer Society]] |isbn=0-8186-2150-8}}</ref>

=== 1993 ===
* While the [[HP 48G]] calculators are labelled ''32K'' or ''128K'' to describe their built-in SRAM capacity in a binary sense, the user manual variably uses the terms ''KB'', ''KBytes'' and ''kilobytes'' in the same meaning.<ref name="HP48_UG">{{cite book |url=http://www.hpcalc.org/details.php?id=3937 |title=HP&nbsp;48G Series – User's Guide (UG) |date=December 1994 |publisher=[[Hewlett-Packard]] |edition=8 |id=HP 00048-90126, (00048-90104) |access-date=2015-09-06 |archive-url=https://web.archive.org/web/20180731183137/https://www.hpcalc.org/details/3937 |archive-date=2018-07-31 |url-status=live |orig-year=1993<!-- edition 1 (1993-05) -->}} [https://web.archive.org/web/20180731183137/https://www.hpcalc.org/details/3937]</ref>
* The enhanced [[command line processor]] [[4DOS 5.00]] introduces the concept of a general size range parameter <code>/[s''min'',''max'']</code> for file selection, recognizing lowercase letters ''k'' and ''m'' as decimal prefixes and uppercase letters ''K'' and ''M'' as binary prefixes.<ref name="4DOS_8.00_HELP"/><ref name="4DOS_5.00_HELP">{{cite book |title=4DOS.DOC 5.00 |title-link=4DOS 5.00 |author-first1=Hardin |author-last1=Brothers |author-first2=Tom |author-last2=Rawson |author-link2=Tom Rawson |author-first3=Rex C. |author-last3=Conn |author-link3=Rex C. Conn |date=1993-11-23 |version=5.00}}</ref>

=== 1994 ===
* Feb: [[Microsoft]] [[Windows 3.1x|Windows for Workgroup 3.11]] [[File Manager (Windows)|File Manager]]<ref name="computerhope1">{{cite web |title=Microsoft Windows History |website=Computerhope.com |url=http://www.computerhope.com/history/windows.htm |access-date=2016-06-23}}</ref> uses MB in a binary sense to describe HDD capacity. Prior versions of Windows only used K in a binary sense to describe HDD capacity.<ref name="computerhope1"/>
* Micropolis 4410 Disk Drive Information<ref>{{cite web|url=http://bitsavers.org/pdf/micropolis/Micropolis_4410_DiskDrive_Information.pdf|title=4110 Drive - SCSI|publisher=[[Micropolis (company)|Micropolis]]|date=1994|access-date=2020-05-16}}</ref>
** "1,052&nbsp;MB Formatted Capacity"
** "Unformatted Per Drive 1,205&nbsp;MB" (133.85&nbsp;MB per surface, 9 read-write heads){{clarify|date=July 2020}}
* The [[HP 200LX]] models use "1MB"/"2MB"/"4MB" in a binary sense to describe their RAM capacity.{{citation needed|date=August 2015}}

=== 1995 ===
* August: The [[International Union of Pure and Applied Chemistry]]'s Interdivisional Committee on Nomenclature and Symbols proposed new prefixes {{brown|kibi}} (from kilobinary), {{brown|mebi}}, {{brown|gibi}}, and {{brown|tebi}} for powers of 1024; using the symbols {{brown|kb}}, {{brown|Mb}}, {{brown|Gb}}, and {{brown|Tb}} respectively (e.g. giving {{brown|kb}}B for {{brown|kibi}}byte).<ref>{{cite web|title=IUCr 1995 Report – IUPAC Interdivisional Committee on Nomenclature and Symbols (IDCNS)|url=http://ww1.iucr.org/iucr-top/cexec/rep95/idcns.htm|website=International Union of Crystallography}}</ref>

=== 1996 ===
* [[FOLDOC]] defines the {{brown|exa}}byte (1&nbsp;{{brown|E}}B) as 1024&nbsp;{{brown|peta}}bytes (1024&nbsp;{{brown|P}}B), with {{brown|peta}}byte used in the binary sense of 1024<sup>5</sup>&nbsp;B.<ref>{{cite web |title=Computing Dictionary |website=Foldoc.org |date=2013-11-04 |url=http://foldoc.org/?query=exabyte |access-date=2016-06-23}}</ref>
* [[Markus Kuhn (computer scientist)|Markus Kuhn]] proposes a system with ''di'' prefixes, like the "{{brown|dikilo}}byte" ({{brown|K<sub>2</sub>}}B) and "{{brown|digiga}}byte" ({{brown|G<sub>2</sub>}}B).<ref name="Kuhn">{{cite web |title=Standardized units for use in information technology |website=Cl.cam.ac.uk |author-first=Markus |author-last=Kuhn |author-link=Markus Kuhn (computer scientist) |date=1996-12-29 |url=https://www.cl.cam.ac.uk/~mgk25/information-units.txt |access-date=2016-06-23}}</ref> It did not see significant adoption.

=== 1997 ===
* January: Bruce Barrow endorses the [[International Union of Pure and Applied Chemistry]]'s proposal for prefixes {{brown|kibi}}, {{brown|mebi}}, {{brown|gibi}}, and {{brown|tebi}} in "A Lesson in Megabytes" in IEEE Standards Bearer,<ref>Bruce Barrow, A Lesson in Megabytes, IEEE Standards Bearer 11, 5, January 1997</ref><ref>{{cite web|title=A Lesson in Megabytes|url=https://www.thierry-lequeu.fr/data/PELS/Comm/Publications/Newsletter/9704/STORY18.HTML|website=La documentation de Thierry LEQUEU}}</ref> but instead using the symbols {{brown|Ki}}, {{brown|Mi}}, {{brown|Gi}}, and {{brown|Ti}}.
* IEEE requires prefixes to take the standard SI meaning (e.g., {{blue|mega}} always to mean 1000<sup>2</sup>). Exceptions for binary meaning ({{brown|mega}} to mean 1024<sup>2</sup>) are permitted as an interim measure (where pointed out on a case-by-case basis) until a binary prefix could be standardised.<ref>{{cite web |title=IEC prefixes and symbols for binary multiples |website=Members.optus.net |url=http://members.optus.net/alexey/prefBin.xhtml |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20161207182048/http://members.optus.net/alexey/prefBin.xhtml |archive-date=2016-12-07 |url-status=dead}}</ref>
* FOLDOC defines the {{brown|zetta}}byte (1&nbsp;{{brown|Z}}B) as 1024&nbsp;{{brown|exa}}bytes (1024&nbsp;{{brown|E}}B)<ref>{{cite web |title=Computing Dictionary |website=Foldoc.org |date=2013-11-04 |url=http://foldoc.org/?query=zettabyte |access-date=2016-06-23}}</ref> and the {{brown|yotta}}byte (1&nbsp;{{brown|Y}}B) as 1024&nbsp;{{brown|zetta}}bytes (1024&nbsp;{{brown|Z}}B).<ref>{{cite web |title=Computing Dictionary |website=Foldoc.org |date=2013-11-04 |url=http://foldoc.org/?query=yottabyte |access-date=2016-06-23}}</ref>

=== 1998 ===
* December: [[International Electrotechnical Commission|IEC]] establishes unambiguous prefixes for binary multiples ({{brown|Ki}}B, {{brown|Mi}}B, {{brown|Gi}}B, {{brown|Ti}}B, {{brown|Pi}}B and {{brown|Ei}}B), reserving {{blue|k}}B, {{blue|M}}B, {{blue|G}}B and so on for their decimal sense. Formally published in January 1999.<ref>{{cite web |title=Definitions of the SI units: The binary prefixes | website=Physics.nist.gov |url=https://physics.nist.gov/cuu/Units/binary.html |quote=These prefixes for binary multiples [...] were first adopted by the IEC as ''Amendment 2 to IEC International Standard IEC 60027-2: Letter symbols to be used in electrical technology – Part 2: Telecommunications and electronics''. The full content of ''Amendment 2'', which has a publication date of 1999-01,&nbsp;... |access-date=2016-06-23 }}</ref>

=== 1999 ===
* [[Donald Knuth]], who uses decimal notation like 1&nbsp;{{blue|M}}B = 1000&nbsp;{{blue|k}}B,<ref name="Knuth">{{cite web |title=The Art Of Computer Programming, Fascicle 1 - MMIX |url=http://www-cs-staff.stanford.edu/~knuth/fasc1.ps.gz |access-date=2016-02-05 |url-status=dead |archive-url=https://web.archive.org/web/20160305014709/http://www-cs-staff.stanford.edu/~knuth/fasc1.ps.gz |archive-date=2016-03-05}}</ref> expresses "astonishment" that the proposal was adopted by the IEC, calling them "funny-sounding", and proposes that the powers of 1024 be designated as "large kilobytes" and "large megabytes" (abbreviated {{brown|KK}}B and {{brown|MM}}B, as "doubling the letter connotes both binary-ness and large-ness").<ref name="Knuth-webpage">{{cite web |title=Knuth: Recent News |website=Cs-staff.stanford.edu |url=http://www-cs-staff.stanford.edu/~knuth/news99.html |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160709230105/http://www-cs-staff.stanford.edu/~knuth/news99.html |archive-date=2016-07-09 |url-status=dead}}</ref> [[Metric double prefix|Double prefix]]es were formerly used in the metric system, however, with a multiplicative meaning ("{{blue|MM}}B" would be equivalent to "{{blue|T}}B"), and this proposed usage never gained any traction.
* In their November 1999 paper,<ref>{{cite report |title=Filling the Memory Access Gap: A Case for On-Chip Magnetic Storage |author-first1=Steven W. |author-last1=Schlosser |author-first2=John Linwood |author-last2=Griffin |author-first3=David F. |author-last3=Nagle |author-first4=Gregory R. |author-last4=Ganger |date=November 1999 |id=CMU-CS-99-174 |citeseerx=10.1.1.36.2518 |url=https://www.cs.cmu.edu/~riedel/ftp/Storage/CMU-CS-99-174_abs.html |access-date=2022-06-01}}</ref> Steven W. Schlosser, John Linwood Griffin, David F. Nagle and Gregory R. Ganger adopt the symbol '''{{brown|Gi}}B''' for {{brown|gibi}}byte and quote data throughput in {{brown|mebi}}bytes per second 
** "...&nbsp;Although these numbers appear to yield a capacity of 2.98&nbsp;{{brown|Gi}}B per sled, the capacity decreases ... This yields an effective capacity of about 2.098&nbsp;{{brown|Gi}}B per sled.&nbsp;..." 
** "maximum throughput ('''{{brown|Mi}}B/s''')"
* The [[IEEE 802.11-1999]] standard introduces the time unit [[TU (time unit)|TU]] defined as 1024&nbsp;μs.<ref name="Maufer2004"/>

== 2000s ==
=== 2001 ===
* IBM, [[z/Architecture]], Reference Summary
** Page 59, list the power of 2 and 16, and their decimal value. There is a column name 'Symbol', which list K&nbsp;(kilo), M&nbsp;(mega), G&nbsp;(giga), T&nbsp;(tera), P&nbsp;(peta) and E&nbsp;(exa) for the power of 2 of, respectively, 10, 20, 30, 40, 50, 60.
* Peuhkuri adopts IEC prefixes in his paper at the 2001 Internet Measurement Conference: "...&nbsp;allows maximum size of 224 that requires 1&nbsp;'''GiB''' of RAM ... or acknowledgement numer [sic] is within 32&nbsp;'''KiB''' range. ... on a PC with Celeron processor with 512&nbsp;'''MiB''' of memory ..."<ref>{{cite conference |title=A method to compress and anonymize packet traces |doi=10.1145/505202.505233 |book-title=Proceedings of the First ACM SIGCOMM Workshop on Internet Measurement – IMW '01 |pages=257 |year=2001 |last1=Peuhkuri |first1=Markus |isbn=978-1581134353 |s2cid=1040777 }}</ref>
* The [[Linux kernel]] uses IEC prefixes.<ref>{{cite web |title=UNITS |date=2001-12-22 |work=[[Manual page (Unix)|Linux Programmer's Manual]] |url=http://www.annodex.net/cgi-bin/man/man2html?units+7 |access-date=2007-05-20 |archive-url=https://web.archive.org/web/20070902124532/http://www.annodex.net/cgi-bin/man/man2html?units+7 |archive-date=2007-09-02 |url-status=usurped |quote=When the Linux kernel boots and says <code>hda: 120064896 sectors (61473 MB) w/2048KiB Cache</code> the MB are megabytes and the KiB are kibibytes.}}</ref><ref>{{cite web |title=Configure.help editorial policy |website=Lwn.net |url=https://lwn.net/2002/0103/a/esr-kibi.php3 |access-date=2016-06-23}}</ref>

=== 2002 ===
* [[Markus Kuhn (computer scientist)|Marcus Kuhn]] introduces the term {{brown|kibi}}hertz to mean 1024&nbsp;Hz.<ref>{{cite web |title=Re: [LEAPSECS&#93; Leap second status? from Markus Kuhn on 2002-11-28 (LEAPSECS at USNO) |website=Ucolick.org |url=http://www.ucolick.org/~sla/navyls/0114.html |access-date=2016-06-23}}</ref>
** "Most embedded clocks (state of the art is still a calibrated 32 {{brown|kibi}}hertz crystal) have a frequency error of at least 10<sup>−5</sup> (10&nbsp;ppm), and therefore drift away from the TAI rate faster than 1 second per week."
* [https://azrael.digipen.edu/~mmead/www/docs/DiffAndPatch.pdf Mackenzie et al 2002]:
** use {{brown|tebi}}byte ({{brown|Ti}}B), {{brown|pebi}}byte ({{brown|Pi}}B), {{brown|exbi}}byte ({{brown|Ei}}B)
** use the symbols {{brown|Zi}}B, {{brown|Yi}}B, accompanied by notes explaining that these are "a GNU extension to IEC 60027-2"
* [[JEDEC]] publishes the standard [[JEDEC memory standards|JESD100B.01]], which lists the prefixes {{brown|K}}, {{brown|M}} and {{brown|G}} qualified "as a prefix to units of semiconductor storage capacity", in "contrast with the SI prefix mega ({{blue|M}}) equal to 10<sup>6</sup>, as in a 1-{{blue|M}}b/s data transfer rate, which is equal to {{val|1000000}} bits per second."  A table lists the binary prefixes {{brown|kibi}} {{brown|Ki}} (2<sup>10</sup>)<sup>1</sup>, {{brown|mebi}} {{brown|Mi}} (2<sup>10</sup>)<sup>2</sup>, {{brown|gibi}} {{brown|Gi}} (2<sup>10</sup>)<sup>3</sup>, {{brown|tebi}} {{brown|Ti}} (2<sup>10</sup>)<sup>4</sup> and the decimal prefixes {{blue|kilo}} (10<sup>3</sup>)<sup>1</sup>, {{blue|mega}} (10<sup>3</sup>)<sup>2</sup>, {{blue|giga}} (10<sup>3</sup>)<sup>3</sup>, {{blue|tera}} (10<sup>3</sup>)<sup>4</sup>.<ref>[http://www.jedec.org/standards-documents/dictionary/terms/mega-m-prefix-units-semiconductor-storage-capacity JEDEC dictionary entry: "mega (M) (as a prefix to units of semiconductor storage capacity)"]</ref><ref>{{citation |title=TERMS, DEFINITIONS, AND LETTER SYMBOLS FOR MICROCOMPUTERS, MICROPROCESSORS, AND MEMORY INTEGRATED CIRCUITS: JESD100B.01 |date=Dec 2002 |url=https://www.jedec.org/standards-documents/docs/jesd-100b01 |publisher=JEDEC Solid State Technology Association |accessdate=2024-01-15 }}</ref>

=== 2003 ===
* The World Wide Web Consortium publishes a Working Group Note describing how to incorporate IEC prefixes into mathematical markup.<ref>{{cite web |title=Units in MathML |website=W3.org |url=http://www.w3.org/TR/2003/NOTE-mathml-units-20031110/#prefixes |access-date=2016-06-23}}</ref>

=== 2004 ===
* 2004 revision of IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Certain Other Units), IEEE Std&nbsp;260.1, incorporates IEC definitions for {{brown|Ki}}B, {{brown|Mi}}B etc., reserving the symbols {{blue|k}}B, {{blue|M}}B etc. for their decimal counterparts.
* Chris Hurley refers to 1.024 milliseconds as a "{{brown|kilo}}{{blue|micro}}second", mixing binary use of the prefix "{{brown|kilo}}" with the conventional decimal prefix {{blue|micro}}.<ref>Hurley, C. (2004). WarDriving: Drive, detect, defend: A guide to wireless security. Elsevier. Page 79</ref>
* Thomas Maufer draws an equivalence between the "{{brown|kilo}}-{{blue|micro}}second" and "Time Unit" (TU) that was introduced by the [[IEEE 802.11-1999]] standard.<ref name="Maufer2004">{{cite book |title=A Field Guide to Wireless LANs: For Administrators and Power Users |author-first=Thomas |author-last=Maufer |date=2004 |publisher=[[Prentice Hall Professional]] |series=The Radia Perlman Series in Computer Networking and Security Series |isbn=9780131014060 |id=0131014064 |page=144 |url=https://books.google.com/books?id=GB-87qyhc8sC&pg=PA142 |quote=The units for the Beacon Interval field are kilo-microseconds (1,024&nbsp;μs). In the IEEE 802.11-1999 specification, the term 'Time Unit' is introduced, and defined such that one Time Unit is equal to 1&nbsp;kμs (i.e., one Time Unit is equal to 1.024&nbsp;ms). |access-date=2015-10-27}}</ref>

=== 2005 ===
* IEC extends binary prefixes to include [[zebi]] (Zi) and [[IEC binary prefixes|yobi]] (Yi)<ref>{{cite web |author-first=Zoë |author-last=Smart |title=Obituary – Anders J. Thor, a universal linguist {{pipe}} IEC e-tech {{pipe}} June 2012 |website=Iec.ch |date=2012-04-07 |url=http://www.iec.ch/etech/2012/etech_0612/fam-5.htm |access-date=2016-06-23 |url-status=dead |archive-url=https://web.archive.org/web/20120702212217/http://www.iec.ch/etech/2012/etech_0612/fam-5.htm |archive-date=July 2, 2012 |df=mdy-all }}</ref>
* IEC prefixes are adopted by the [[IEEE]] after a two-year trial period.
** On March 19, 2005, the IEEE standard [[IEEE 1541]]-2002 (Prefixes for Binary Multiples) was elevated to a full-use standard by the IEEE Standards Association after a two-year trial period.<ref>{{cite web |title=IEEE-SA STANDARDS BOARD STANDARDS REVIEW COMMITTEE (RevCom) MEETING AGENDA |date=2005-03-19 |url=http://standards.ieee.org/board/rev/305agenda.html |access-date=2007-02-25 |quote='''1541–2002''' (SCC14) IEEE Trial-Use Standard for Prefixes for Binary Multiples ''[No negative comments received during trial-use period, which is now complete; Sponsor requests elevation of status to full-use.]'' <u>Recommendation</u>: Elevate status of standard from trial-use to full-use. Editorial staff will be notified to implement the necessary changes. The standard will be due for a maintenance action in 2007. |archive-url=https://web.archive.org/web/20070922215418/http://standards.ieee.org/board/rev/305agenda.html |archive-date=2007-09-22 |url-status=dead}}</ref>

=== 2006 ===
* The [[BIPM]] publishes the 8th SI Brochure including the note<ref>{{SIbrochure8th|page=121}}</ref>
*: "These SI prefixes refer strictly to powers of 10. They should not be used to indicate powers of 2 [...]. The IEC has adopted prefixes for binary powers [...]. Although these prefixes are not part of the SI, they should be used in the field of information technology to avoid the incorrect usage of the SI prefixes."
* In addition to the ''k'' and ''m'' decimal as well as the ''K'' and ''M'' binary prefixes, [[4DOS 7.50]].141 (2006-12-24) adds support for ''g'' and ''G'' as decimal respective binary prefixes in [[4DOS variable function|variable function]]s and size range parameters.<ref name="4DOS_8.00_HELP"/>

=== 2007 ===
* [[Windows Vista]] still uses the binary conventions (e.g., 1 KB = 1024 bytes, 1 MB = 1048576 bytes) for file and drive sizes, and for data rates<ref>{{cite web |title=Why does Explorer use the term KB instead of KiB? |website=Microsoft developer blogs |date=June 11, 2009 |url=https://devblogs.microsoft.com/oldnewthing/20090611-00/?p=17933 |access-date=2024-07-06}}</ref>
* [[GParted]] uses IEC prefixes for partition sizes
* [[Advanced Packaging Tool]] and [[Synaptic Package Manager]] use standard SI prefixes for file sizes
* IBM uses "exabyte" to mean 1024<sup>6</sup> bytes.<ref>{{cite web |title=A brief history of virtual storage and 64-bit addressability | website=[[IBM]] |url=https://www.ibm.com/docs/en/zos-basic-skills?topic=storage-brief-history-virtual-64-bit-addressability |access-date=2024-07-06}}</ref> "Each address space, called a 64-bit address space, is '''16 exabytes (EB)''' in size; an exabyte is slightly more than one billion gigabytes. The new address space has logically 2<sup>64</sup> addresses. It is 8 billion times the size of the former 2-gigabyte address space, or 18,446,744,073,709,600,000 bytes."
* Edward Michael McDonald III uses the terms zebibyte, yobibyte to mean 2<sup>70</sup> and 2<sup>80</sup>  bytes, respectively, pointing out the need to distinguish between decimal and binary prefixes when dealing with the storage capacity of high performance computers.<ref>{{cite thesis |url=https://diginole.lib.fsu.edu/islandora/object/fsu:180854/datastream/PDF/view |last=McDonald |first=E. M. |date=2007 |title=Designing Reliable Large-Scale Storage Arrays |degree=MSc |publisher=[[Florida State University]]}}</ref>

=== 2008 ===
* The US [[NIST|National Institute of Standards and Technology]] guidelines prohibit use of SI prefixes k, M, ... in the binary sense, and suggest IEC prefixes Ki, Mi ... for binary multiples<ref name="sp330">{{cite book |editor-first1=Barry N. |editor-last1=Taylor |editor-first2=Ambler |editor-last2=Thompson |title=The International System of Units (SI) |publisher=[[National Institute of Standards and Technology]] |location=Gaithersburg, MD |page=23 |year=2008 |url=http://physics.nist.gov/Pubs/SP330/sp330.pdf |access-date=2008-06-18 |archive-url=https://web.archive.org/web/20080625011144/http://physics.nist.gov/Pubs/SP330/sp330.pdf |archive-date=2008-06-25 |url-status=dead}}</ref>
** p.&nbsp;29, "The names and symbols for the prefixes corresponding to 2<sup>10</sup>, 2<sup>20</sup>, 2<sup>30</sup>, 2<sup>40</sup>, 2<sup>50</sup>, and 2<sup>60</sup> are, respectively: {{brown|kibi}}, {{brown|Ki}}; {{brown|mebi}}, {{brown|Mi}}; {{brown|gibi}}, {{brown|Gi}}; {{brown|tebi}}, {{brown|Ti}}; {{brown|pebi}}, {{brown|Pi}}; and {{brown|exbi}}, {{brown|Ei}}. Thus, for example, one {{brown|kibi}}byte is also written as 1&nbsp;{{brown|Ki}}B = 2<sup>10</sup>&nbsp;B = 1024&nbsp;B, where B denotes the unit ''byte''. Although these prefixes are not part of the SI, they should be used in the field of information technology to avoid the non-standard usage of the SI prefixes."
* The binary prefixes are defined in IEC Standard [[IEC 80000-13]], formally incorporating them into the [[ISO/IEC 80000|ISO/IEC series of standards of quantities and units]].
* [[IBM WebSphere]] describes data transfer using unambiguous IEC prefixes<ref>{{cite web |title=IBM WebSphere MQ File Transfer Edition Version 7 Release 0 |page=200 |website=IBM |url=https://public.dhe.ibm.com/software/integration/wmq/docs/fteV7.0.4/PDFs/wmqfte.pdf |access-date=2024-07-06}}</ref>
** "Current file. The name of the file currently being transferred. The part of the individual file that has already been transferred is displayed in B, {{brown|Ki}}B, {{brown|Mi}}B, {{brown|Gi}}B, or {{brown|Ti}}B along with total size of the file in parentheses. The unit of measurement displayed depends on the size of the file. B is bytes per second. {{brown|Ki}}B/s is kibibytes per second, where 1 {{brown|kibi}}byte equals 1024 bytes. {{brown|Mi}}B/s is {{brown|mebi}}bytes per second, where 1 {{brown|mebi}}byte equals {{val|1048576}} bytes. {{brown|Gi}}B/s is {{brown|gibi}}bytes per second where 1 {{brown|gibi}}byte equals {{val|1073741824}} bytes. {{brown|Ti}}B/s is {{brown|tebi}}bytes per second where 1 {{brown|tebi}}byte equals {{val|1099511627776}} bytes."
** "The rate the file is being transferred in {{brown|Ki}}B/s ({{brown|kibi}}bytes per second, where 1 {{brown|kibi}}byte equals 1024 bytes.)"

=== 2009 ===
* [[Apple Inc.]] uses the SI decimal definitions for capacity (e.g., 1 kilobyte = 1000 bytes) in the [[Mac OS X v10.6]] operating system to conform with standards body recommendations and avoid conflict with hard drive manufacturers' specifications.<ref>{{cite web |title=News – Snow Leopard: 1&nbsp;GB = 1000&nbsp;MB |publisher=macprime.ch |date=2009-06-19 |url=http://www.macprime.ch/news/article/snow-leopard-1-gb-1000-mb/ |access-date=2009-08-29}}</ref><ref>{{cite web |title=How Mac OS X reports drive capacity |publisher=Apple |date=2009-08-27 |url=http://support.apple.com/kb/TS2419 |access-date=2009-08-30}}</ref>
* Frank Löffler and co-workers report disk size and computer memory in tebibytes.<ref>{{cite web |title=BENCHMARKING PARALLEL I/O PERFORMANCE FOR A LARGE SCALE SCIENTIFIC APPLICATION ON THE TERAGRID |author-first1=Frank |author-last1=Löffler |author-first2=Gabrielle |author-last2=Allen|author2-link=Gabrielle Allen |author-first3=Erik |author-last3=Schnetter |website=Cct.lsu.edu |url=https://www.cct.lsu.edu/~gallen/Preprints/CS_Loeffler09a.pre.pdf |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160817181756/https://www.cct.lsu.edu/~gallen/Preprints/CS_Loeffler09a.pre.pdf |archive-date=2016-08-17 |url-status=dead}}</ref>
**"For the largest simulations using 2048 cores this sums up to about 650 GiB per complete checkpoint and about 6.4&nbsp;TiB in total (for 10 checkpoints)."
* the SourceForge web site<ref name="autogenerated1">{{cite journal |title=How many bytes are in a GB? |journal=ISS Technology Update |volume=9 |issue=1 |publisher=[[Hewlett-Packard]] |url=https://support.hpe.com/hpesc/public/docDisplay?docLocale=en_US&docId=emr_na-c02022732 |access-date=2022-06-29}}</ref>
** "For example, in 2009, the SourceForge web site reported file sizes using binary prefixes for several months before changing back to SI prefixes but switching the file sizes to powers of ten."
* The binary prefixes, as defined by IEC&nbsp;80000-13, are incorporated into [[ISO&nbsp;80000-1]], including a note that "SI prefixes refer strictly to powers of 10, and should not be used for powers of 2."<ref>{{cite web|title=ISO 80000-1:2009(en) Quantities and units – Part 1: General (§3.17)|url=https://www.iso.org/obp/ui/#iso:std:iso:80000:-1:ed-1:v1:en|access-date=2022-11-08}}</ref> In ISO 80000-1, the application of the binary prefixes is not limited to computer technology. For example, 1&nbsp;KiHz = 1024&nbsp;Hz.

== 2010s ==
=== 2010 ===
* The [[Ubuntu (operating system)|Ubuntu operating system]] uses the SI prefixes for base-10 numbers and IEC prefixes for base-2 numbers as of the 10.10 release.<ref>{{cite web |title=Ubuntu implements units policy, will switch to base-10 units in future release |website=Neowin.net |url=https://www.neowin.net/news/ubuntu-implements-units-policy-will-switch-to-base-10-units-in-future-release/ |access-date=2016-06-23}}</ref><ref>{{cite web |title=UnitsPolicy – Ubuntu Wiki |website=Wiki.ubuntu.com |url=https://wiki.ubuntu.com/UnitsPolicy |access-date=2016-06-23}}</ref>
* Baba Arimilli and co-workers use the pebibyte (PiB) for computer memory and disk storage and exbibyte (EiB) for archival storage<ref>{{cite web |title=The PERCS High-Performance Interconnect |author-first1=Baba |author-last1=Arimilli |display-authors=etal |website=Spcl.inf.ethz.ch |url=http://spcl.inf.ethz.ch/Publications/.pdf/ibm-percs-network.pdf |access-date=2016-06-23}}</ref>
** "Blue Waters will comprise more than 300.000 POWER7 cores, more than 1&nbsp;PiB memory, more than 10&nbsp;PiB disk storage, more than 0.5&nbsp;EiB archival storage, and achieve around 10 PF/s peak performance."
* [[Hewlett-Packard|HP]] publishes a leaflet explaining use of SI and binary prefixes "To reduce confusion, vendors are pursuing one of two remedies: they are changing SI prefixes to the new binary prefixes, or they are recalculating the numbers as powers of ten."<ref name="autogenerated1"/>
** "For disk and file capacities, the latter remedy is more popular because it is much easier to recognize that 300&nbsp;GB is the same as 300,000&nbsp;MB than to recognize that 279.4&nbsp;GiB is the same as 286,102&nbsp;MiB."
** "For memory capacities, binary prefixes are more natural. For example, reporting a Smart Array controller cache size of 512&nbsp;MiB is preferable to reporting it as 536.9&nbsp;MB."
** "HP is considering modifying its storage utilities to report disk capacity with correct decimal and binary values side-by-side (for example, '300&nbsp;GB (279.4&nbsp;GiB)'), and report cache sizes with binary prefixes ('1&nbsp;GiB')."

=== 2011 ===
* The [[GNU|GNU operating system]] uses the SI prefixes for base-10 numbers and IEC prefixes for base-2 numbers as of the parted-2.4 release (May 2011).
** "specifying partition start or end values using MiB, GiB, etc. suffixes now makes parted do what I want, i.e., use that precise value, and not some other that is up to 500KiB or 500MiB away from what I specified. Before, to get that behavior, you would have had to use carefully chosen values with units of bytes ('B') or sectors ('s') to obtain the same result, and with sectors, your usage would not be portable between devices with varying sector sizes. This change does not affect how parted handles suffixes like KB, MB, GB, etc."<ref>{{cite web |title=parted-2.4 released [stable&#93; |website=Lists.gnu.org |date=2011-05-18 |url=http://lists.gnu.org/archive/html/info-gnu/2011-05/msg00012.html |access-date=2016-06-23}}</ref>
** "Note that as of parted-2.4, when you specify start and/or end values using IEC binary units like 'MiB', 'GiB', 'TiB', etc., parted treats those values as exact, and equivalent to the same number specified in bytes (i.e., with the 'B' suffix), in that it provides no 'helpful' range of sloppiness. Contrast that with a partition start request of '4GB', which may actually resolve to some sector up to 500MB before or after that point. Thus, when creating a partition, you should prefer to specify units of bytes ('B'), sectors ('s'), or IEC binary units like 'MiB', but not 'MB', 'GB', etc."<ref>{{cite web|url=https://www.gnu.org/software/parted/manual/parted.html |title=Parted User's Manual |website=Gnu.org |access-date=2016-06-23}}</ref>
* On its Archive Project Request Form, the [[University of Oxford]] uses IEC prefixes: "The initial amount of data to be archived (MiB GiB TiB )"
* The IBM Style Guide permits IEC prefixes or "SI prefixes" if used consistently and explained to the user<ref>DeRespinis, F., Hayward, P., Jenkins, J., Laird, A., McDonald, L., & Radzinski, E. (2011). The IBM style guide: conventions for writers and editors. IBM Press.</ref> "Whether you choose to use IEC prefixes for powers of 2 and SI prefixes for powers of 10, or use SI prefixes for a dual purpose ... be consistent in your usage and explain to the user your adopted system."

=== 2012 ===
* June: Toshiba describes data transfer rates in units of MiB/s.<ref>{{cite press release |format=PDF |title=Toshiba Announces High-Performance, Power-Efficient Solid State Drives Targeted at Broad Range of Notebook, Desktop, Embedded and Commercial Markets |website=Storage.toshiba.com |url=http://storage.toshiba.com/docs/press-releases/thnsnf_release.pdf?sfvrsn=12 |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20160806174056/http://storage.toshiba.com/docs/press-releases/thnsnf_release.pdf?sfvrsn=12 |archive-date=2016-08-06 |url-status=dead}}</ref> In the same press release, SSD storage capacity is given in decimal gigabytes, accompanied by the footnote "One Gigabyte (GB) means 10<sup>9</sup> = 1,000,000,000 bytes using powers of 10. A computer operating system, however, reports storage capacity using powers of 2 for the definition of 1&nbsp;GB = 1,073,741,824 bytes and therefore shows less storage capacity"
* July: Ola BRUSET and Tor Øyvind VEDAL are granted a patent citing the binary unit KiHz to mean 1024&nbsp;hertz<ref>{{cite web |title=Patent WO2012098399A2 – Low-power oscillator – Google Patents |website=Google.com |url=https://patents.google.com/patent/WO2012098399A2/en |access-date=2016-06-23}}</ref>
* The Minnesota Supercomputing Institute of the [[University of Minnesota]] uses IEC prefixes to describe its supercomputing facilities<ref>{{cite web |title=High-Performance Computing Resources |website=Minnesota Supercomputing Institute |url=https://www.msi.umn.edu/hpc |access-date=2013-09-28 |url-status=dead |archive-url=https://web.archive.org/web/20131002142026/https://www.msi.umn.edu/hpc |archive-date=2013-10-02}}</ref>
** "Itasca is an HP Linux cluster with 1,091 HP ProLiant BL280c G6 blade servers, each with two quad-core 2.8&nbsp;GHz Intel Xeon X5560 'Nehalem EP' processors sharing 24&nbsp;GiB of system memory, with a 40-gigabit QDR InfiniBand (IB) interconnect. In total, Itasca consists of 8,728 compute cores and 24&nbsp;TiB of main memory."
** "Cascade consists of a Dell R710 head/login node, 48&nbsp;GiB of memory; eight Dell compute nodes, each with dual X5675 six-core 3.06&nbsp;GHz processors and 96&nbsp;GiB of main memory; and 32 Nvidia M2070 GPGPUs. A compute node is connected to four GPGPUs, each of which has 448 3.13&nbsp;GHz cores and 5&nbsp;GiB of memory. Each GPU is capable of 1.2 single-precision TFLOPS and 0.5 double-precision TFLOPs."
* [[Phidget|Phidgets Inc]] describes PhidgetSBC3 as a "Single board computer running Debian 7.0 with 128&nbsp;MiB DDR2 SDRAM, 1&nbsp;GiB Flash, integrated 1018 and 6 USB 2.0 High Speed 480Mbits/s ports".
* IBM's Customer Information Center uses IEC prefixes to disambiguate<ref>{{cite web |title=Data storage values |work=3592 Enterprise Tape System |publisher=IBM |date=2021-03-08 |url=https://www.ibm.com/docs/en/3592-enterprise-tape?topic=overview-data-storage-values |access-date=2024-07-06}}</ref>
** "To reduce the possibility of confusion, this information center represents data storage using both decimal and binary units. Data storage values are displayed using the following format:#### decimal unit (binary unit). By this example, the value 512 terabytes is displayed as: 512&nbsp;TB (465.6&nbsp;TiB)"

=== 2013 ===
* February: Toshiba distinguishes unambiguously between decimal and binary prefixes by means of footnotes. Hybrid drives MQ01ABD100H and MQ01ABD075H are described as having a buffer size of 32&nbsp;{{brown|Mi}}B.<ref>{{cite web |title=SSD/HDD Storage Products Product Catalog Mar. 2013 |url=http://www.semicon.toshiba.co.jp/download/docs_pdf/BCE0106_catalog.pdf |access-date=2014-03-07 |url-status=dead |archive-url=https://web.archive.org/web/20140308003708/http://www.semicon.toshiba.co.jp/download/docs_pdf/BCE0106_catalog.pdf |archive-date=2014-03-08}}</ref>
** "1&nbsp;{{blue|M}}B (megabytes) = {{val|1,000,000}} bytes, 1&nbsp;{{blue|G}}B ({{blue|giga}}bytes) = {{val|1,000,000,000}} bytes, 1&nbsp;{{blue|T}}B ({{blue|tera}}bytes) = {{val|1,000,000,000,000}} bytes"  
** "{{brown|Ki}}B ({{sic|{{brown|kebi}}bytes}}) = {{val|1,024}} (2<sup>10</sup> bytes), {{brown|Mi}}B ({{brown|mebi}}bytes) = {{val|1,048,576}} (2<sup>20</sup>) bytes, {{brown|Gi}}B (gibibytes) = {{val|1,073,741,824}} (2<sup>30</sup>) bytes".  
* March: Kevin Klughart uses the {{brown|zebi}}byte ({{brown|Zi}}B) and {{brown|yobi}}byte ({{brown|Yi}}B) as units for maximum volume size<ref>{{cite web |title=Data storage architecture extension system and method – KLUGHART KEVIN MARK |website=Freepatentsonline.com |date=March 21, 2013 |url=http://www.freepatentsonline.com/y2013/0073747.html |access-date=2016-06-23 |last1=Mark |first1=Klughart }}</ref>
* [[PRACE]] Best Practice Guide uses IEC prefixes for net capacity (300&nbsp;{{brown|Ti}}B) and throughput (2&nbsp;{{brown|Gi}}B/s).<ref>{{cite web |title=Best Practice Guide – Anselm – PRACE Research Infrastructure |at=2.5 Filesystems|website=Prace-project.eu |date=2016-06-03 |url=https://prace-ri.eu/training-support/best-practice-guides/best-practice-guide-anselm/ |access-date=2022-06-29}}</ref>
* Nicla Andersson, of Sweden's National Supercomputer Centre, Sweden, refers to the NSC's Triolith as having "42.75&nbsp;{{brown|Ti}}B memory" and "75&nbsp;{{brown|Ti}}B/s aggregate memory BW" and to a 2018 [[DARPA]] target of "32–64&nbsp;{{brown|Pi}}B memory"<ref>{{cite web |title=TSEA28, Datorteknik Y |website=Nsc.liu.se |url=https://www.nsc.liu.se/~nican/education/tsea28_2013.pdf |access-date=2016-06-23}}</ref>
* August: Mitsuo Yokokawa, of [[Kobe University]], describes the Japanese K Computer as having "1.27&nbsp;(1.34)&nbsp;PiB" of memory.<ref>{{cite web |title=Experiences of the Development of the Supercomputers |website=Tmrc2013.riec.tohoku.ac.jp |url=http://www.tmrc2013.riec.tohoku.ac.jp/TMRC_Keynote.pdf |access-date=2016-06-23}}</ref>
* The official file server of the [[University of Stuttgart]] reports file sizes in {{brown|gibi}}bytes ({{brown|Gi}}B) and {{brown|tebi}}bytes ({{brown|Ti}}B).<ref>{{cite web |title=Index of / |website=Ftp.uni-stuttgart.de |url=http://ftp.uni-stuttgart.de/ |access-date=2016-06-23}}</ref>
* In their book ''IBM Virtualization Engine TS7700 with R3.0'', Coyne et al. use IEC prefixes to distinguish them from decimal prefixes.<ref>{{cite book |title=IBM Virtualization Engine TS7700 with R3.0 |author-first1=Larry |author-last1=Coyne |author-first2=Katja |author-last2=Denefleh |author-first3=Joe |author-last3=Hew |author-first4=Rex |author-last4=Newton |author-first5=Aderson |author-last5=Pacini |author-first6=David |author-last6=Reich |author-first7=Michael |author-last7=Scott |author-first8=Chen |author-last8=Zhu |page=104 |url=https://books.google.com/books?id=2WbJAgAAQBAJ&pg=PA104 |access-date=2016-06-23|isbn=9780738438580 |date=October 15, 2013 |publisher=IBM Corporation, International Technical Support Organization }}</ref> Examples are
** "Larger, 1.1&nbsp;{{blue|G}}B (1&nbsp;{{brown|Gi}}B) internal buffer on Model&nbsp;E06/EU6, 536.9&nbsp;{{blue|M}}B (512&nbsp;{{brown|Mi}}B) for Model E05, 134.2&nbsp;{{blue|M}}B (128&nbsp;{{brown|Mi}}B) for Model J1A"
** "Up to 160 {{brown|Mi}}bit/sec. native data rate for the Models E06 and EU6, four times faster than the model J1A at 40&nbsp;{{brown|Mi}}bit/sec. (Up to 100&nbsp;{{brown|Mi}}bit/sec. for the Model&nbsp;E05)"
* [http://www.maplesoft.com/products/maple/new_features/maple17/performance.aspx Maple 17] uses {{brown|Mi}}B and {{brown|Gi}}B as units of memory usage.
* November: The online computer dictionary FOLDOC defines the {{blue|kilo}}byte as one thousand (1000) bytes, the {{blue|mega}}byte as one million (1000<sup>2</sup>) bytes, and the {{blue|giga}}byte as one billion (1000<sup>3</sup>) bytes.<ref>{{cite web |title=Computing Dictionary |website=Foldoc.org |date=2013-11-04 |url=http://foldoc.org/megabyte |access-date=2016-06-23}}</ref>

=== 2014 ===
* February: Rahul Bali writes<ref>{{cite web |title=linuxfederation.com |website=Linuxfederation.com |url=http://www.linuxfederation.com/10-powerful-supercomputers-running-linux/ |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20140530162742/http://www.linuxfederation.com/10-powerful-supercomputers-running-linux/ |archive-date=May 30, 2014 |url-status=dead |df=mdy-all }}</ref>
** "the [Sequia (IBM)] contains in total 1,572,864 processor cores with 1.5&nbsp;PiB memory"
** "The total CPU plus coprocessor memory [of the Tianhe-2 (NUDT)] is 1,375 TiB."
* [[CDBurnerXP]] states disc sizes in mebibytes (MiB) and gibibytes (GiB), clarifying that "in Windows, if you see GB or MB it usually refers to GiB or MiB respectively".
* September: HP 3PAR StoreServ Storage best practices guide uses binary prefixes for storage and decimal prefixes for speed.<ref>{{cite web |title=HP 3PAR StoreServ Storage best practices guide |website=8.hp.com |url=http://www8.hp.com/h20195/v2/GetPDF.aspx%2F4AA4-4524ENW.pdf |access-date=2016-06-23 |archive-url=https://web.archive.org/web/20141104065530/http://www8.hp.com/h20195/v2/GetPDF.aspx%2F4AA4-4524ENW.pdf |archive-date=November 4, 2014 |url-status=dead |df=mdy-all |quote=Units of measure: All units of storage (capacity) are calculated base 2 (×&nbsp;1,024). Therefore: 1&nbsp;KiB = 1,024&nbsp;bytes ... All units of performance (speed) are calculated base 10 (×&nbsp;1000). Therefore: 1&nbsp;KB = 1,000&nbsp;bytes&nbsp;...}}</ref>

=== 2017 ===
* K Liao and co-authors approximate the year as 30 mebiseconds (30 Mis)<ref>{{cite conference |last1=Liao |first1=K. |last2=Moffat |first2=A. |last3=Petri |first3=M. |last4=Wirth |first4=A. |date=February 2017 |title=A cost model for long-term compressed data retention |book-title=Proceedings of the Tenth ACM International Conference on Web Search and Data Mining |pages=241–249 |doi=10.1145/3018661.3018738}}</ref>

=== 2019 ===
* The [[BIPM]] publishes the 9th SI brochure, confirming the position from its 8th brochure (published in 2006), with the note<ref>{{SIbrochure9th|page=143}}</ref>
*: "The SI prefixes refer strictly to powers of 10. They should not be used to indicate powers of&nbsp;2 [...]"

== 2020s ==
=== 2020 ===
* A Californian court finds that, as the [[NIST]] specifies that prefixes such as "{{blue|G}}" are decimal rather than binary, and that California law specifies that the NIST definitions of measure "shall govern ... transactions in this state", and because the vendor of a 64&nbsp;{{blue|G}}B flash drive with 64 billion bytes indicated on the packaging of the drive that 1&nbsp;{{blue|G}}B = {{val|1,000,000,000}} bytes, they did not deceive consumers into believing that the drive had 64&nbsp;×&nbsp;1024&nbsp;×&nbsp;1024&nbsp;×&nbsp;1024 bytes.<ref>[https://www.courthousenews.com/wp-content/uploads/2020/01/flashdrives.pdf Order granted motion to dismiss amended complaint without leave to amend, 22 January 2020]</ref>

=== 2021 ===
* Ainslie, Halvorsen and Robinson point out the parallel with the confusion between a [[One-third octave#Base 2|one-third octave]] and a [[One-third octave#Base 10|one-tenth decade]] in acoustics.<ref>{{cite journal |date=January 2022 |orig-date=2021-11-09 |title=A terminology standard for underwater acoustics and the benefits of international standardization. |journal=[[IEEE Journal of Oceanic Engineering]] |publisher=[[IEEE]] |volume=47 |issue=1 |pages=179–200 |bibcode=2022IJOE...47..179A |doi=10.1109/JOE.2021.3085947 |issn=0364-9059 |eissn=1558-1691 |s2cid=243948953 |doi-access=free |author-last1=Ainslie |author-first1=Michael A. |author-last2=Halvorsen |author-first2=Michele B. |author-last3=Robinson |author-first3=Stephen P. }} (22 pages)</ref>
*: "The near coincidence between ten octaves and three decades (2<sup>10</sup> ≈ 10<sup>3</sup>) is identical to the one that causes confusion in the computer industry by use of the term '{{brown|kilo}}byte' to mean 1024&nbsp;B ... when the internationally accepted use of the prefix {{blue|kilo}} requires it to mean 1000&nbsp;B."

=== 2022 ===
* February: IEEE 1541 is amended to include the prefixes {{brown|zebi}} and {{brown|yobi}}.<ref>[https://standards.ieee.org/ieee/1541/6867/ IEEE 1541-2021 IEEE Standard for Prefixes for Binary Multiples]</ref>
* November: The additional decimal prefixes ''{{blue|ronna}}'' for 1000<sup>9</sup> and ''{{blue|quetta}}'' for 1000<sup>10</sup> are adopted by the [[International Bureau of Weights and Measures]] (BIPM).<ref>{{cite web |title=List of Resolutions for the 27th meeting of the General Conference on Weights and Measures |url=https://www.bipm.org/documents/20126/64811223/Resolutions-2022.pdf |archive-url=https://web.archive.org/web/20221118153958/https://www.bipm.org/documents/20126/64811223/Resolutions-2022.pdf |archive-date=2022-11-18 |url-status=dead |date=2022-11-18 |access-date=2022-11-18 }}</ref><ref>{{cite journal |title=How many yottabytes in a quettabyte? Extreme numbers get new names |author-last=Gibney |author-first=Elizabeth |date=2022-11-18 |journal=[[Nature (journal)|Nature]] |volume= |issue= |pages= |doi=10.1038/d41586-022-03747-9 |pmid=36400954 |s2cid=253671538 |url=https://www.nature.com/articles/d41586-022-03747-9 |access-date=2022-11-21|url-access=subscription }}</ref> Binary counterparts to ''{{blue|ronna}}'' and ''{{blue|quetta}}'' were suggested in a consultation paper of the Consultative Committee for Units (CCU) for the [[International Committee for Weights and Measures]] as ''{{brown|robi}}'' ({{brown|Ri}}, 1024<sup>9</sup>) and ''{{brown|quebi}}'' ({{brown|Qi}}, 1024<sup>10</sup>).<ref>{{cite journal |title=Reply to 'Facing a shortage of the Latin letters for the prospective new SI symbols: alternative proposal for the new SI prefixes' |author-last=Brown |author-first=Richard J. C. |date=2022-04-27 |journal={{ill|Accreditation and Quality Assurance|de}} |volume=27 |issue= 3|pages=143–144 |doi=10.1007/s00769-022-01499-7|s2cid=248397680 }}</ref><ref>{{cite journal |title=A further short history of the SI prefixes |journal=[[Metrologia]] |department=Letter to the editor |author-first=Richard J. C. |author-last=Brown |date=2023 |orig-date=2022-02-08, 2022-04-01, 2022-11-24 |volume=60 |issue=1 |page=013001 |publisher=[[BIPM]] & [[IOP Publishing Ltd]] |id=013001 |doi=10.1088/1681-7575/ac6afd |bibcode=2023Metro..60a3001B |s2cid=253966045 |doi-access=free }} (1+4 pages)</ref>

=== 2025 ===
* February: IEC 80000-13:2025<ref>{{cite web|title=IEC 80000-13:2025|url=https://webstore.iec.ch/en/publication/87379|publisher=[[International Electrotechnical Commission]]|access-date=2025-02-12}}</ref> revises the previous edition of this standard with the addition of new prefixes {{brown|robi}} (symbol {{brown|Ri}}) and {{brown|quebi}} ({{brown|Qi}}) for binary multiples.

== References ==
{{reflist|30em}}

{{Timelines of computing}}

{{DEFAULTSORT:Timeline Of Binary Prefixes}}
[[Category:Computing timelines|B]]
[[Category:Units of information]]