The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, and, in early models, a cassette deck.
Development of the system began in 1976, and it was demonstrated and sold as the first personal computer for the masses at the January 1977 Consumer Electronics Show. The name "PET" was suggested by Andre Souson after he saw the Pet Rock in Los Gatos, and stated they were going to make the "pet computer". It was backronymed to Personal Electronic Transactor. In a 1995 retrospective, Byte magazine—and subsequently many others—referred to the PET, Apple II and TRS-80 collectively as the "1977 trinity" of pioneering personal computers.