Microcomputers (personal computers)Microcomputers are the most commontype of computers used by people today,whether in a workplace, at school or on thedesk at home. The term “microcomputer”was introduced with the advent of singlechip microprocessors. The term"microcomputer" itself is now practically ananachronism.
These computers include:•Desktop computers – A case and a display,put under and on a desk.
•In-car computers (“carputers”) – Built into acar, for entertainment, navigation, etc.
A separate class is that of mobile devices:•Laptops, notebook computers and Palmtop computers –Portable and all in one case. Varying sizes, but other thansmartbooks expected to be “full” computers withoutlimitations.
•Tablet computer – Like laptops, but with a touch-screen,sometimes entirely replacing the physical keyboard.
•Smartphones, smartbooks andPDAs (personal digital assistants) – Small handheld computerswith limited hardware.
•Programmable calculator– Like small handhelds, butspecialized on mathematical work.•Handheld game consoles – The same as game consoles, butsmall and portable.
Minicomputers (midrange computers)A minicomputer (colloquially, mini) is a class of multi-user computers that lies in the middle range of thecomputing spectrum, in between the smallest multi-user systems (mainframe computers) and the largestsingle-user systems (microcomputers or personalcomputers). The contemporary term for this class ofsystem is midrange computer, such as the higher-endSPARC, POWER and Itanium -based systems fromOracle Corporation, IBM and Hewlett-Packard. E.g.-Laboratory computers
Mainframe computersThe term mainframe computer was created todistinguish the traditional, large, institutionalcomputer intended to service multiple users from thesmaller, single user machines. These computers arecapable of handling and processing very largeamounts of data quickly. Mainframe computers areused in large institutions such as government, banksand large corporations. They are measured in MIPS(million instructions per second) and respond to up to100s of millions of users at a time.
Embedded computersEmbedded computers are computers that are a part of amachine or device. Embedded computers generally execute aprogram that is stored in non-volatile memory and is onlyintended to operate a specific machine or device. Embeddedcomputers are very common. Embedded computers aretypically required to operate continuously without being resetor rebooted, and once employed in their task the softwareusually cannot be modified. An automobile may contain anumber of embedded computers; however, a washing machineand a DVD player would contain only one. The centralprocessing units (CPUs) used in embedded computers are oftensufficient only for the computational requirements of thespecific application and may be slower and cheaper than CPUsfound in a personal computer.
SupercomputerA supercomputer is focused on performing tasks involving intensenumerical calculations such as weather forecasting, fluiddynamics, nuclear simulations, theoretical astrophysics, andcomplex scientific computations. A supercomputer is a computerthat is at the frontline of current processing capacity, particularlyspeed of calculation. The term supercomputer itself is ratherfluid, and the speed of todays supercomputers tends to becometypical of tomorrows ordinary computer.