Your personal computer is a microcomputer. Technically, a microcomputer is a computer in which the CPU (central processing unit, the brains of the computer) is contained on one single chip, a microprocessor. Most workstations are also considered microcomputers, for the same reason, although some personal computers are as fast as the fastest workstation. And a computer used by more than one person (a multi-user computer) is still a microcomputer as long as it has a microprocessor for its CPU.
The next step up from a microcomputer On size, speed, capabilities, and price) is a minicomputer. Then a mainframe. Then a supercomputer.