It came out in 1974 and was the basis of the MITS Altair 8800, for which two guys named Bill Gates and Paul Allen wrote BASIC, and millions of people began to realize that they, too, could have their very own, personal, computer.
Todd Dailey [CC By-SA 2.0] via Wikimedia Commons The Altair 8800, based on the Intel 8080, was the first commercially successful home hobbyist PC.