A payline is a 'line' on slot machine reels on which symbols must line up on in order to win. Some slot machines have only 1 payline, some have 3, others have 5, 9 and even 15! Generally speaking, you must pay a coin to play each line on a machine, but have the option of not playing all available lines. So, on a 3 line machine, you can play the center line for one coin - the center line and the line above it for two coins - or all 3 lines for 3 coins. If you don't play a specific line and a winning combination comes up on it - then you don't win. Classic slot machines have 3 reels and only 1 line - a horizontal payline that goes through the middle of each reel. You may be able to wager more than one coin per spin on these games - but the amount will apply to wins on the same payline. (You win more by betting more, but your chances of winning stay the same) Other 3 reel slots often have three paylines, one in the middle, one above it, and one below it. Betting 1 coin activates the middle payline, betting 2 coins opens up 2 paylines, and 3 coins plays all 3 lines on a spin. 5 reel slot machines typically have quite a few paylines, from 5 to 15. These paylines aren't necessarily straight lines - there's diagonal matches and lines that actually bend. How the lines go differs from machine to machine, but the lines should be marked clearly on each game. .