The story of Atari is a fascinating one. They were pioneers of this innovative age, doing to console gaming what Microsoft did to the personal computer. They created the first "official" video game (excluding Computer Space and other video game-like experiments of the sixties and seventies), the upright Pong (which generated hundreds of dollars in quarters weekly at Andy Capp's Bar & Restaurant) upon its initial release. They even created home versions and variations of their Pong game (simply attach a small box to your television to play), including Home Pong and Super Pong. But their real pride and joy was their Atari Video Computer System, with interchangeable cartridges and many famous games you remember from coin-op arcades.
The Atari VCS wasn't the first gaming system with interchangable cartridges, though. The Fairchild Channel F, released several years before the 1977 launch of the VCS, carried with it a handful of cartridges, mostly Pong-like, that required a plastic overlay on your television screen to play properly. But they were the first gaming system to be a staple, almost a requirement, in the modern late-seventies home.
The technical requirements for Atari VCS games is slim. The ported Pac-Man and Space Invaders looked much better at the arcade. Sometimes the characters weren't much more than a large green dot on the screen. But the games were all there, in their downplayed glory... Mario Brothers, Tron, Galaga, and many, many others. This was perhaps the VCS's claim to fame: the ability to play famous coin-op games without having all your laundry quarters gobbled up.
Shortly after the VCS's release, other video game systems were released, such as the Intellivision and Colecovision units. These carried with them better graphics and sounds, generally the same games (but with higher resolution, more faithful to their coin-op companions), as well as some new, exclusive titles. To combat these systems, Atari released subsequent, competitive consoles, the 5200 Supersystem and backwards-compatible 7800 Prosystem. They even released a re-packaged VCS, re-named the 2600 (because that was the system's number in the Atari Catalog). But even through all these technical improvements, the VCS/2600 was still the top-seller. In all, there were a staggering 1,600+ Atari VCS/2600 games, maybe more. But as impressive as this sounds... the huge number of games was probably the VCS's ultimate downfall.
The VCS/2600 remained popular despite the technical advancements (much like the way Game Boy remains popular) but when the market became oversaturated in the early eighties with mediocre Atari games, the VCS/2600 took a major plummet, and the Atari Corporation suffered great losses. Even still, the legacy and lessons of Atari (especially the VCS/2600), a pioneer in gaming consoles, has left it's influence for all future gaming experiences.