Endgames
The techniques that decide games once the pieces come off: key positions, opposition, and fortress ideas.
Bishop vs. Knight Endgames
One of chess's oldest debates: which minor piece is better once most of the other pieces are gone? The honest answer is "it depends entirely on the pawns."
King and Queen vs. King
The single most common winning technique in all of chess: with a queen and your own king, a lone enemy king can always be forced into checkmate.
King and Rook vs. King
The second essential basic checkmate: confine the enemy king to a shrinking rectangle with the rook, then use your own king to force it to the edge.
Lucena Position
The most famous winning technique in rook endgames: "building a bridge" with your rook so your king can safely escort a pawn to the queening square.
Opposition & Key Squares
The single most fundamental technique in king-and-pawn endgames: whichever king controls the critical squares in front of the pawn usually decides the whole game.
Philidor Position
The defensive counterpart to the Lucena Position: how the weaker side holds a draw in a rook endgame by controlling the third rank, then checking from behind.
Two Bishops Checkmate
A fundamental checkmating technique every player must learn: driving a lone king to the edge of the board using nothing but two bishops and a king.
Zugzwang
German for "compulsion to move": a position where any legal move makes things worse, and the only real wish is to be allowed to pass — which chess never allows.