1971
Intel announces the 4004, the first commercial single-chip microprocessor
Intel placed an advertisement in Electronic News announcing "a new era of integrated electronics" — the Intel 4004, a 4-bit central processing unit on a single chip, originally designed for the Busicom calculator. It packed roughly 2,300 transistors and is widely credited as the first commercially available microprocessor.
Source: Wikipedia — Intel 4004
