The fifty-move rule acts as a practical safeguard against infinitely long games. The counter resets every time a pawn moves or a piece is captured, since both actions irreversibly change the position. If neither event occurs within fifty moves by each side, either player may claim a draw.
This rule has been important in chess history, particularly in certain endgame studies. Some endgames that are theoretically winning require more than fifty moves without a capture or pawn move to convert, leading to debates about whether the rule should be extended for specific material configurations.
In practical play, the fifty-move rule most often comes into effect in rook endgames or other technically difficult endings where the stronger side struggles to make progress. Awareness of the move count can influence both the attacker's urgency and the defender's strategy.