This document summarizes different classes of computers. It describes microcomputers, which include desktops, in-car computers, and game consoles. Mobile devices like laptops, tablets, smartphones and PDAs are also microcomputers. Minicomputers, also called midrange computers, have more power than microcomputers but less than mainframes. Mainframes are large, institutional computers that can process vast amounts of data for many users simultaneously. Embedded computers are built into devices and machines to control their functions. Supercomputers perform extremely complex scientific calculations and are at the forefront of processing power.