An Arabic-derived word meaning arrangement, formation, or deployment. A typical position that frequently appears after following book moves in the opening. A branching point where players begin to devise their own plans

Short-term piece exchanges and combinations

One of the endgame principles in chess. The rule states that when a passed pawn is advancing toward promotion, the opponent's rook should be placed behind the pawn (on the promotion side)

Tempo refers to the turn (one's turn to move). The plural form is tempi. Gaining a tempo means forcing the opponent to make defensive moves while advancing your pieces to favorable positions

A move that threatens to capture an opponent's piece or deliver checkmate on the next move. Creating a situation that would lead to significant loss or defeat if the opponent doesn't respond

Changing the move order to ultimately reach the same position. Example: English Opening → Queen's Gambit. In a broad sense, includes Reversal of moves

The principle that to break through the opponent's defense, one weakness is not enough; creating a second weakness splits the defense and leads to victory. The opponent must divide defensive resources, resulting in one weakness being exploited