Supercomputers are the most powerful type of computer.These are special high-capacity computers used by very large organizations.The speed of computing is fast.
Mainframe computers occupy specially wired,air-conditioned rooms.Although not nearly as powerful as supercomputers,mainframe computers are capable of great processing speeds and data storage.
Minicomputers are refrigeratorsized machines.Medium-sized companies or departments of large companies typically use them for specific purpose.
Microcomputers are the least powerful ,yet the most widely used and fastest-growing type of computer.

Microcomputer is the most common type.

Microcomputers have six types:desktop,media center,notebook,tablet PC,and handheld computers.