View source for Half-open file

{{Short description|Chess terminology}}
{{Chess diagram
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|  |  |rd|  |  |  |  |  
|pd|pd|  |  |  |pd|pd|pd
|  |  |  |  |  |  |  |  
|  |  |  |pd|pd|  |  |  
|  |  |  |  |pl|  |  |  
|  |  |pl|  |  |  |  |pl
|pl|pl|  |  |  |pl|pl|  
|  |  |  |rl|  |  |  |  
|Both the c- and d-files are half-open, with each player's rook in position to capitalize.
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In [[chess]], a '''half-open file''' (or '''semi-open file''') is a {{chessgloss|file}} with [[pawn (chess)|pawns]] of only one color.  The half-open file can provide a line of attack for a player's [[rook (chess)|rook]] or [[Queen (chess)|queen]]. A half-open file is generally exploited by the player with no pawns on it. 

Many [[Opening (chess)|openings]], such as the [[Sicilian Defense]], aim to complicate the position. In the main line Sicilian, 1.e4 c5 2.Nf3 d6 (or 2...e6, or 2...Nc6) 3.d4 cxd4 4.Nxd4, White obtains a half-open d-file, but Black can pressure White along the half-open c-file.

In positions where White has no pawns on a file but Black has one pawn or more on that file, the position is considered to be half-opened for White. In cases where Black has no pawns on a file but White has one or more pawns on that file, the position is considered to be half-opened for Black.

A ''pawn break'' occurs when a pawn captures or advances in a way that opens or half-opens one or more files. The demolition of the [[pawn structure]] is a common theme in positions with half-open files, since [[doubled pawns]] or [[isolated pawns]] may create half-open files. 
{{AN chess|pos=toc}}

==Example==
{{Chess diagram
|tleft
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|  |bd|  |  |  |rd|kd|  
|  |pd|  |  |  |  |  |pd
|  |  |  |  |  |  |  |  
|  |nl|  |pd|  |  |  |  
|pl|  |nd|bl|nd|  |qd|  
|  |  |  |  |pl|  |pl|  
|rl|  |  |  |  |pl|kl|nl
|  |  |  |  |  |  |  |ql
|Black to move 
}}
The game [[Loek van Wely]]–[[Judit Polgár]], Hoogeveen, 1997<ref>{{cite web |url=http://www.chessgames.com/perl/chessgame?gid=1111353 |title=Loek Van Wely vs. Judit Polgar, It (cat.16) 1997 |website=[[Chessgames.com]] }}</ref> demonstrates the power of half-open files in attacks. Despite having one fewer pawn than White, Black's possession of two powerful half-open files (her rook on the f-file and queen on the g-file) gives her a winning advantage ({{em|diagram}}).

Black played 

{{pad}}'''30... Rxf2+{{chesspunc|!}}''' 

and White resigned, anticipating 31.Rxf2 Qxg3+ 32.Kf1 Qxf2{{chessAN|#}}.
{{clear}}

==See also==
* [[Open file]]

==References==
{{reflist}}

'''Bibliography'''
* {{Citation
 |last=Alburt|first=Lev|author-link=Lev Alburt
 |last2=Lawrence|first2=Al|author-link2=Al Lawrence (chess writer)
 |title=Chess Rules of Thumb
 |year=2003
 |publisher=Chess Information and Research Center 
 |isbn=1-889323-10-1}}
* {{cite book
 |last1=Hooper 
 |first1=David  
 |author-link1=David Vincent Hooper
 |last2=Whyld 
 |first2=Kenneth 
 |author-link2=Kenneth Whyld
 |title=[[The Oxford Companion to Chess]]
 |publisher=[[Oxford University Press]]
 |edition=2nd
 |year=1996
 |orig-year=First pub. 1992
 |page=165
 |isbn=0-19-280049-3 }}

{{chess}}

[[Category:Chess terminology]]
[[Category:Chess strategy]]