The Intellivision is a home video game console released by Mattel Electronics in 1979. The name Intellivision is a portmanteau of "intelligent television". Development of the console began in 1977, the same year as the introduction of its main competitor, the Atari 2600. In 1984, Mattel sold their video game assets to a former Mattel Electronics executive and investors who formed an entity that became INTV Corporation. Games development started in 1978 and continued until 1990 when Intellivision was discontinued. From 1980 to 1983 over 3 million Intellivision units were sold.