In chess and chess-like games, the endgame (or end game or ending) is the stage of the game when few pieces are left on the board.
The line between middlegame and endgame is often not clear, and may occur gradually or with the quick exchange of a few pairs of pieces. The endgame, however, tends to have different characteristics from the middlegame, and the players have correspondingly different strategic concerns. In particular, pawns become more important as endgames often revolve around attempting to promote a pawn by advancing it to the eighth rank. The king, which has to be protected in the middlegame owing to the threat of checkmate, becomes a strong piece in the endgame. It can be brought to the center of the board and act as a useful attacking piece.
Compared to chess opening theory, which changes frequently, giving way to middlegame positions that fall in and out of popularity, endgame theory is less subject to change. Many people have composed endgame studies, endgame positions which are solved by finding a win for White when there is no obvious way to win, or a draw when it seems White must lose.
Usually in the endgame, the stronger side (the one with more material using the standard piece point count system) should try to exchange pieces (knights, bishops, rooks, and queens), while avoiding the exchange of pawns. This generally makes it easier to convert a material advantage into a won game. The defending side should strive for the opposite.
Chess players classify endgames according to the type of pieces that remain.
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