When was Galaga released?

Context: Galaga is a 1981 fixed shooter arcade video game developed and published by Namco. In North America, it was released by Midway Manufacturing. It is the sequel to Galaxian, Namco's first major video game hit in arcades. Controlling a starship, the player is tasked with destroying the Galaga forces in each stage while avoiding enemies and projectiles. Some enemies can capture a player's ship via a tractor beam, which can be rescued to transform the player into a "dual fighter" with additional firepower.

Answer: Galaga was released in 1981 as a fixed shooter arcade video game developed and published by Namco.