The Atari 2600 (or Atari Video Computer System or Atari VCS before November 1982) is a home video game console from Atari, Inc. Released on September 11, 1977, it is credited with popularizing the use of microprocessor-based hardware and games contained on ROM cartridges, a format first used with the Fairchild Channel F in 1976. This contrasts with the older model of having dedicated hardware that could play only those games that were physically built into the unit. The 2600 was bundled with two joystick controllers, a conjoined pair of paddle controllers, and a game cartridge: initially Combat,^[5] and later Pac-Man.^[6]

Entering 1975, Atari was already successful with its arcade games and dedicated home consoles that recreated these games (such as Pong), but there were increasing costs and risks in these adaptations. The company wanted to push for a home console that could play multiple games, necessitating a microprocessor which were still costly. Breadboard development of this system, nicknamed "Stella", coincided with the release of the MOS Technology 6502 microprocessor, one of the first low-cost processors to hit the market; Atari worked with MOS Technology and established the use of their less-powerful MOS Technology 6507 for the platform. Further, Atari's Jay Miner led development of the Television Interface Adapter (TIA) chip which performed all the graphics and audio output to the television display necessary for the platform. These were coupled with the necessary input/output ports with a ROM cartridge reader and joystick controllers to complete the system. Atari's system was still in development when the Fairchild Channel F was announced, leading Atari's owner Nolan Bushnell to sell Atari to Warner Communications in 1976, in exchange for a cash infusion to speed up development. Initial production for the console's November 1977 release was made at Atari's Sunnyvale, California location while future units were produced in Hong Kong and Taiwan.

The Atari 2600 sold moderately well in its first few years, relying principally on ports of arcade games, both from Atari and titles licensed from others. Disagreements over sales potential of the 2600 led Bushnell to leave Atari in 1978. Following the release of Atari's licensed version of Space Invaders from Taito in 1980, the 2600 became widely successful, leading to the creation of third-party game developers, notably Activision, and competition from other home console makers such as Coleco and Mattel Electronics by 1982. Atari invested heavily in two games for the 2600, Pac-Man and E.T. the Extra-Terrestrial, that would become commercial failures for Atari and contributed to the video game crash of 1983. The 2600 was shelved as the industry recovered, while Warner sold off the home console division of Atari to Commodore CEO Jack Tramiel. The new Atari Corporation under Tramiel re-released a low-cost streamlined version of the 2600 in 1986, as well as the Atari 7800 that boasted backwards compatibility with the 2600. Ultimately, production of the Atari 2600 and other home consoles ended in 1992, with an estimated 30 million units of the 2600 sold as of 2004.