The Commodore PET is a line of home/personal computers produced starting in 1977 by Commodore International. The system combined a MOS 6502 microprocessor, Commodore BASIC in read only memory (ROM), a keyboard, a computer monitor and (in early models) a cassette deck for data and program storage in a single all-in-one case.
Development of the system began in 1976 and a prototype was demonstrated in January 1977 at the Consumer Electronics Show (CES). A series of problems meant that production versions did not begin to arrive until December 1977, by which time the TRS-80 and Apple II had already begun deliveries. The close release dates of the three machines led Byte Magazine to refer to them collectively as the “1977 trinity”.
The original PET design underwent a series of significant updates, adding more memory, a better keyboard, larger screens and other modifications. The systems were a top-seller in the Canadian and United States educational markets, as well as European business uses. The PET formed the basis for Commodore’s entire 8-bit product line, including the Commodore 64.