query: When was the first CPU developed?
passage: Intel 4004
The Intel 4004 is a 4-bit central processing unit (CPU) released by Intel Corporation in 1971. It was the first commercially available microprocessor by Intel,[2] and the first in a long line of Intel CPUs.
passage: History of Digital Equipment Corporation
With the company established and a successful product on the market, DEC turned its attention to the computer market once again as part of its planned "Phase II". In August 1959, Ben Gurley started design of the company's first computer, the PDP-1. In keeping with Doriot's instructions, the name was an initialism for "Programmable Data Processor", leaving off the term "computer". As Gurley put it, "We aren't building computers, we're building 'Programmable Data Processors'." The prototype was first shown publicly at the Joint Computer Conference in Boston in December 1959. The first PDP-1 was delivered to Bolt, Beranek and Newman in November 1960, and formally accepted the next April. The PDP-1 sold in basic form for $120,000, or about $900,000 in 2011 US dollars. By the time production ended in 1969, 53 PDP-1s had been delivered.