IBM Model AT personal computer, c 1984.
© Science Museum / Science & Society Picture Library
IBM dominated the personal computer market in the early to mid 1980s, particularly the busines user end of the market. The AT (Advanced Technology) machine launched in 1984 was an advance on the earlier PC, with a new, more powerful Intel 80286 microprocesor and increased RAM. The AT was also introduced at a lower price than many experts anticipated, starting at $3995.