There are four main types of computers: super computers, mainframe computers, minicomputers, and microcomputers. Super computers can perform the most complex computational tasks and are used for scientific and engineering applications. Mainframe computers are large computers used by large organizations for critical tasks like data processing. Minicomputers are smaller than mainframes but larger than microcomputers, and are used by small businesses and firms for specific departmental tasks. Microcomputers include desktops, laptops, tablets, phones, and are the most widely used and affordable type for general personal and work use.