Exchange (chess) to as a "recapture". Commonly, the word "exchange" is used when the pieces exchanged are of the same type or of about equal value, which is an "even exchange". According to chess tactics, a bishop and a knight are usually of about equal value. If the values of the pieces exchanged are not equal, then the player who captures the higher value of piece(s) can be said to be "up the exchange" or "wins the exchange", while the opponent who captures the lower value of piece(s) is "down the exchange" or "loses the exchange". Exchanges occur very frequently in chess,
Fairy chess piece "pao" and "vao" (derived from the Chinese cannon) and the "mao" (derived from the horse). Those derived from the cannon are distinguished by moving as a hopper when capturing, but otherwise moving as a rider. Pieces from xiangqi are usually circular disks, labeled or engraved with a Chinese character identifying the piece. Pieces from shogi (Japanese chess) are usually wedge-shaped chips, with kanji characters identifying the piece. Fairy pieces vary in the way they move, but some may also have other special characteristics or powers. The joker (in one of its definitions) mimics the last move made by the opponent.