Rock Paper Scissors is a hand game usually played between two people, in which each player simultaneously forms one of three shapes with an outstretched hand. These shapes are “rock” (a simple fist), “paper” (a flat hand), and “scissors” (a fist with the index and middle fingers together forming a V).

The players show their shapes on the 4th prime. This is after a count of 3 and on the verbal cue of ‘Shoot’ this can also be a non-verbal cue. If both players choose the same shape, the game is tied and is immediately replayed to break the tie. Players agree to the best of series prior to competing. In official WRPSA matches games are played in best 3 of 5.

The game is often used as a choosing method in a way similar to coin flipping, drawing straws, or throwing dice. Unlike truly random selection methods, however, RPS can be played with a degree of skill by recognizing and exploiting non-random behavior in opponents.