Rock Paper Scissors

Rock Paper Scissors traces back to hand games recorded in Han Dynasty China around 200 BCE and reached Japan as Jan-ken by the 17th century. Three gestures form a balanced cycle: rock crushes scissors, scissors cuts paper, paper covers rock. Each option beats one and loses to another, so no single move dominates. The game resolves disputes and fills breaks with equal fairness. Game theory classifies it as a simultaneous zero-sum game with a mixed-strategy Nash equilibrium. Throw your first hand and play the cycle.

1. Open Rock Paper Scissors and choose your throw: rock, paper, or scissors. The computer picks its move at the same time.
2. Rock is represented by a closed fist. It beats scissors and loses to paper.
3. Scissors is shown with two extended fingers. It beats paper and loses to rock.
4. Paper is a flat open hand. It beats rock and loses to scissors.
5. If both players throw the same gesture, the round is a draw and you play again.
6. The first player to reach five wins takes the match. Track the score and adjust your strategy as the round count grows.

• Both players reveal their gesture simultaneously. No take-backs after the reveal.
• Rock beats scissors, scissors beats paper, and paper beats rock. The cycle is perfectly symmetric.
• Matching gestures produce a draw. No points are awarded, and the round repeats.
• Each win adds one point to the winner's tally. Draws score zero for both sides.
• The first player to reach five wins ends the match.
• No communication or signaling is allowed during the throw in competitive play.

• Avoid fixed patterns. Humans unconsciously repeat sequences after wins and switch after losses, which a sharp opponent can exploit. Vary your throws deliberately.
• Statistically, men throw rock most often on the first move, at roughly 35 percent frequency. Paper is the statistically strongest opening response against an unknown male opponent.
• After a player loses, they tend to switch to the gesture that just beat them. If you won with rock and they lost with scissors, expect them to throw rock next, so lead with paper.
• After a win, players often repeat their winning gesture. If you just lost to paper, expect paper again and throw scissors.
• Treat the computer AI as random unless you detect a pattern. Against a random opponent, no strategy beats pure randomness, so focus on your own habits instead.
• In best-of formats, track the opponent's throw distribution. If one gesture appears more than 40 percent of the time, bias your response toward the counter to that gesture.

• Rock Paper Scissors Lizard Spock: A five-gesture version popularized by the TV show The Big Bang Theory, adding lizard and Spock to create a 10-relationship cycle with more strategic depth.
• Best-of-three match: The standard competitive format where the first player to win two rounds takes the match, reducing the impact of a single lucky throw.
• Tic-Tac-Toe: Another quick decision game with perfect symmetry, where both players can force a draw with optimal play.

• The three-way cycle is perfectly balanced, so no move is inherently stronger than another.
• Rounds last seconds, making it ideal for quick breaks and tiebreakers.
• Reading an opponent's habits adds a psychological layer to a mathematically simple game.
• The hand-gesture format requires no equipment and works anywhere.
• The mixed-strategy equilibrium from game theory gives the game real intellectual depth beneath its simple surface.

Play Rock Paper Scissors online for free on Clasica Games. Click rock, paper, or scissors to throw your hand, watch the computer reveal its move instantly, and race to five wins. The interface tracks the score and round count so you can spot patterns in the AI's choices. No download or account needed. Throw your first hand and play the cycle.

Rock Paper Scissors wraps game theory into a three-gesture cycle. Read your opponent, vary your throws, and race to five wins. Throw your first hand and play the oldest decision game in the world.

• Rock Paper Scissors history - Britannica
• Rock Paper Scissors rules and game theory