The Complete Chess Course From Beginning To Winning Chess! (2016)
The Basic Rules of Chess
Check and Checkmate
The king is the most important piece in chess.
The basic method of winning a game of chess is to attack the hostile king in such a way that it cannot escape. This is called “checkmate.” (The king is actually not captured; its inability to escape from attack is what constitutes the checkmate.)
Any attack by a piece or pawn directly on a king is called a “check.” When a king is checked, it must immediately get out of check. The king cannot be allowed to remain in check.
If it is a player’s turn to move and his king is not in check, he cannot make any move that exposes the king to check. The king must never come within the capturing range of hostile pieces.
There are three ways to get out of check:
(1) to capture the unit that is giving check;
(2) to move the king out of the line of attack - but not into the line of attack of some other unit;
(3) to interpose one of your own units between the king and the hostile unit that is giving check.
If none of these three methods can be applied, then the king is checkmated.
In Diagrams 23 and 24 the black king was in check, but it was possible to get out of check. In Diagram 25 the attacked king is able to escape; but in Diagram 26 the attacked king is checkmated. (D)
White’s queen is checking the black king. Black has a choice of three different ways of getting his king out of check.
Black has captured the white queen, getting out of check. Black could also have moved his king, or interposed his rook.
Black’s king is checkmated. White’s queen is giving check and Black’s king cannot capture the white queen, which is protected by a white bishop. Having no flight square, or way of interposing a friendly unit, Black’s king is trapped.
Black’s king is in check from White’s rook but it has a “loophole.” By playing his king diagonally forward to the right, Black escapes from the check.
The positions in Diagrams 26, 27, and 28 are all examples of checkmate. In each case the checking piece cannot be captured; the attacked king cannot move out of the capturing range of the hostile forces; and no friendly unit can be interposed on the line of attack between the checking unit and the checked king. (D)
Black’s king is in check from White’s rook and has no escape, as its own pawns block the exit. This is an example of checkmate.
White’s king is checkmated. White has no escape from the black bishop’s check. Note that Black’s knight and bishops command all the possible squares available to White’s king, and White cannot interpose any of his own units.
This is a special kind of check, caused by removing a unit to unmask a line of attack by another unit. For example, in Diagram 29 White’s bishop can give check without moving; the check is “discovered” by moving the white rook which has been blocking the diagonal. The result appears in Diagram 30. (D)
White can give a discovered check with his bishop by moving his rook.
By moving his rook, White has opened up an attacking line for a discovered check by his bishop.
This is a discovered check with an added feature: the piece that unmasks an attacking line for the discovered check also gives check. (D)
By moving his bishop to give check, White can give double check with his queen.
As Black’s king cannot move out of check, he is checkmated. The double check was devastating.
The double check is the most difficult kind of check to meet, as capture or interposition is impossible. For if either checking unit is captured, the other unit continues to give check. Similarly, an interposition to one check still leaves the other check functioning.
The only possible reply to a double check, then, is to move the attacked king. Where this is not feasible, the king is checkmated.