In video gaming, an achievement is a meta-goal defined outside of a game's parameters. Achievements may be implemented by a platform, or solely within the game itself.
From Wikipedia:
In video gaming parlance, an achievement, also sometimes known as a trophy, badge, award, stamp, medal or challenge, is a meta-goal defined outside of a game's parameters. Unlike the systems of quests or levels that usually define the goals of a video game and have a direct effect on further gameplay, the management of achievements usually takes place outside the confines of the game environment and architecture.1 Meeting the fulfillment conditions, and receiving recognition of fulfillment by the game, is referred to as unlocking the achievement. Despite the usual connotations of the term, unlocking an achievement does not generally pave the way for future actions with the same achievement.
