power pellet

First appearing in limited release in Tokyo arcades on this day in 1980 and originally called Puck Man (see also) from the onomatopoetic gobbling om-nom paku paku taberu—though that was changed once developers realised that the potential and temptation for defacement would be high, especially in foreign markets, Pac-Man was an instant and transformative hit with players, helping to expand and legitimise the video game industry. Working for Namco, programmer and game designer Toru Iwatani was inspired to make the protagonist by a pizza with a slice taken out. Much more gaming history and lore at Kotaku at the link above.