It typically contains three or more “reels,” with various symbols on each. Which images appear along the pay line determines how much money you win or the payout.
You succeed if every reel displays the same winning image along the pay line. Which images fall on the pay line, a line in the center of the viewing window, decide whether you win or lose.
The player spins a set of reels with printed graphics by pulling a handle. Computer-controlled machines have almost entirely supplanted traditional mechanical designs. Slot machine technology has advanced significantly over the years.