Game over is a message in video games which signals to the player that their play is over, usually received negatively such as losing all of one's lives, or either follows its score after successful completion of a game. The phrase has since been turned into quasi-slang, usually describing an event that will cause harm, injury, or bad luck to a person.
The phrase was used as early as the 1950s in devices such as electromechanical pinball machines, which would light up the phrase with a lamp (lightbulb).
Before the advent of home consoles and personal computing, arcades were the predominant platform for playing games, which required users to deposit a token or coin (traditionally a quarter, in the U.S.) into an arcade game machine in order to play. Players would usually be given a finite number of lives (or attempts) to progress through the game, the exhaustion of which would usually result in the display of the message "Game over" indicating that the game had ended. The phrase might also be followed by the message "Play Again?" and a prompt asking the player to insert additional tokens to prevent the game from terminating and instead allowing the player to continue their progress. The message can also be seen flashing on certain arcade games while in attract mode, until a player inserts a credit; at this point the message would change to the number of credits inserted and "Press 1 or 2 player start", or some variation thereof.
As these games were ported to home consoles, the "Game over" screen and "Continue?" prompt remained, but often required only the press of a button to keep the game going; while the video game industry shifted away from being arcade-focused to being home gaming-focused, the inclusion of such a screen was no longer as critical since it offered no financial benefit. However, the concept of Game Over remained imbued in the medium thereafter as a way to add an element of risk: a player who is unsuccessful at carrying out the game's objective (possibly repeatedly) will be faced with such a screen and be forced to start over from either the beginning of the game or a previous, saved state.