The Atari 2600 is a video game console released in October 1977 by Atari, Inc. It is credited with popularizing the use of microprocessor-based hardware and cartridges containing game code, instead of having non-microprocessor dedicated hardware with all games built in. The first game console to use this format was the Fairchild Channel F; however, the Atari 2600 receives credit for making the plug-in concept popular among the game-playing public.
Info gleaned from Wikipedia
SEGA megadrive advert from 1991.
The Mega Drive is a fourth-generation video game console released by Sega in Japan in 1988 and Europe in 1990. The console was released in North America in 1989 under the name Genesis, as Sega was unable to secure legal rights to the Mega Drive name in that region. The Mega Drive, heavily marketed as “16-bit” due to its hardware, was Sega’s fifth home console and the successor to the Sega Master System, with which it is electronically compatible.
The Mega Drive was the first of its generation to achieve notable market share in Europe and North America. It was a direct competitor of the TurboGrafx-16 (which was released one year earlier in Japan under the name PC Engine, but at about the same time as the Genesis in North America) and the Super Nintendo Entertainment System (which was released two years later). The Mega Drive began production in Japan in 1988 and ended with the last new licensed game being released in 2002 in Brazil.
1979 UK and Ireland commercial for the Philips Videopac Computer Games System.
The Magnavox Odyssey², known in Europe as the Philips Videopac G7000, in Brazil as the Philips Odyssey, in the United States as the Magnavox Odyssey² and the Philips Odyssey², and also by many other names, is a video game console released in 1978.
In the early 1970s, Magnavox was an innovator in the home video game industry. They succeeded in bringing the first home video game system to market, the Odyssey, which was quickly followed by a number of later models, each with a few technological improvements. In 1978, Magnavox, now a subsidiary of North American Philips, released the Odyssey², their new second-generation video game console.
The Atari 2600, released in October 1977, is the video game console credited with popularizing the use of microprocessor based hardware and cartridges containing game code, instead of having non-microprocessor dedicated hardware with all games built in. The first game console to use this format was the Fairchild Channel F. However, it was the Atari 2600 that made the plug-in concept popular among the game-playing public.