The Atari 2600 was originally launched in 1977 as the Atari Video Computer System, usually shortened to Atari VCS.
Atari used the VCS name because the machine was a programmable console that played interchangeable cartridges. It followed Atari’s earlier Pong-style dedicated machines and competed with systems such as the Fairchild Channel F and RCA Studio II.
The console was renamed the Atari 2600 in 1982, when Atari introduced the Atari 5200. The new number fit Atari’s emerging numerical product naming scheme and distinguished the older system from its successor.
A common mix-up is treating “Atari 2600” as the original launch name. In fact, Atari VCS appeared on the first packaging and hardware. The console became one of the defining home systems of the early 1980s, helped by cartridge games such as Asteroids, Missile Command, and Adventure.