A payline is a line or pattern on a slot machine that determines where matching symbols must appear for a player to win. Traditional slots often have a single payline, while modern video slots can have multiple paylines that run in various directions, such as horizontally, diagonally, or even in zigzag patterns. To win, players must land a set of matching symbols along an active payline, and the payout depends on the specific symbols and their alignment. Paylines add structure to slot games, as they define the possible winning combinations.