Half-open line

	a	b	c	d	e	f	G	H
8th									8th
7th									7th
6th									6th
5									5
4th									4th
3									3
2									2
1									1
	a	b	c	d	e	f	G	H

Opening of the half-open c-line to b4 – b5

A half-open line refers to a line in the game of chess , where only one or more farmers are the same color (see. Pawn structures ). Half-open lines are a common positional feature. The missing second pawn on this line determines the appropriate use of the heavy pieces .

Strategic characteristics

The side whose pawn no longer exists can use the half-open line to put pressure on the opposing position. This is usually done by filling this line with heavy pieces, or by blocking the opposing pawn. In order to increase the effectiveness of the heavy pieces placed on half-open lines, one often strives either to completely open these lines or to try to conquer the opposing pawn on the line.

The position of the example diagram has developed from the so-called "Karlsbad pawn structure" (see also: Exchange variant in the Queen's Gambit ), in which both sides try to use the respective half-open line for the rooks with a minority attack . White tries to open the line with the pawn lever b4 – b5, or to weaken the pawn on c6 after an exchange; Black's analogous plan can be initiated with f5 – f4.

Openings

Half- open lines often emerge from the opening , typically in half-open games , when pawns are exchanged early on:

• Sicilian Defense (swap black pawn c5 for white pawn d4)
• Scottish game (exchange e5 for d4)
• Exchange variant of the Spanish game (half-open d-file for Black after d7xc6)
• Accepted King's Gambit (exchange e5 for f4)