Although there is no rigid definition, a microcomputer (sometimes shortened to micro) is most often taken to mean a computer with a microprocessor (µP) as its CPU. Another general characteristic of these computers is that they occupy physically small amounts of space.
The microcomputer came after the minicomputer, most notably replacing the many distinct components that made up the minicomputer's CPU with a single integrated microprocessor chip. Such early models were primitive, the earliest microprocessors being little more than general-purpose calculator chips. However, as microprocessor design advanced rapidly from the early 1970s onwards, microcomputers in turn grew faster and cheaper, resulting in an explosion in their popularity.
Whilst the microcomputer may have taken over from older-style designs in many cases, its most significant effects are to have widened access to computers, and to have expanded their usage into completely new areas.
The first microcomputer was the Japanese Sord Computer Corporation's SMP80/08 (1972), which was followed by the SMP80/x (1974). The French developers of the Micral N (1973) filed their patents with the term "Micro-ordinateur", a literal equivalent of "Microcomputer", to designate a solid state machine designed with a microprocessor.
In April 1972, Sord Computer Corporation (now Toshiba Personal Computer System Corporation) developed the SMP80/08, the first microcomputer. It used the Intel 8008 microprocessor, which it was developed in tandem with. The SMP80/08, however, did not have a commercial release. After the first general-purpose microprocessor, the Intel 8080, was announced in April 1974, Sord announced the SMP80/x, the first microcomputer to use the 8080, in May 1974. The SMP80/x marked a major leap toward the popularization of microcomputers.