Mobility is an important concept in chess. It refers simply to how many moves the pieces have available. Pieces that are cramped or pushed back are not very mobile.
Mobility is an important advantage. A cramped position is often a lost position. Mobility helps create an attack and also aids in defence.
Piece mobility is an important aspect of counter-play and compensation for a sacrifice. A pawn sacrifice may often give up the pawn (material) in return for greater space and thereby greater piece mobility.
Related Chess Tactics
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