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Desktop computer

A desktop computer is an independent personal computer that is made especially for use on a desk in an office or home. The term is used mainly to distinguish this type of personal computer from portable computers and laptops, but also to distinguish other types of computers like the PDA, server or mainframe.

Desktops are currently the more affordable and most common computers, and are frequently used by businesses, schools, households and other organizations. Nearly all modern desktop computers are modular, meaning that the components can easily be replaced or upgraded. A desktop computer can also refer to a computer whose case is oriented horizontally (usually, the monitor is placed on top of the case). Such cases are called Desktops as opposed to Towers.

Contents

History

Desktop Computers were vastly produced in the late 1970's and 1980's as there were no laptop or PDA computers available at the time. The first widely sold and successful desktop computer was the Apple II introduced in 1977 by Apple Computer. In 1981 IBM entered the desktop computer market with their IBM PC. In the mid 1990's desktop computers were widely advertised for their amount of power useful for graphics and multimedia. Studios, Universities and the Government prefer to use desktop computers today because they are more powerful and more expandable than a laptop computer.

Hardware

The hardware in a desktop computer is modular, making it easy for someone with intermediate knowledge of a computer to modify one. The internal hardware of a basic desktop computer consists of RAM, CPU, a motherboard, a graphics card and a sound card as well as additional onboard cards for Ethernet and other ports.

Desktop computers usually have a separate monitor. User-input peripherals such as keyboards, mice are attatched to the computer's ports, as well as other peripherals such as printers. Most of the functionality is contained within the case, but some components can be either either external or internal (such as various storage devices or modems). The case is often placed on or under the desk. Sometimes, it can be placed underneath the monitor depending on the size and shape.

Desktop computers are generally more affordable than notebook computers. This is because no extra effort is needed to miniaturize the components, or manufacture components that use up less power. However, desktop computers do use up more power than notebook computers.

Components

  • Fan
  • Motherboard
  • Hard drive
  • CD-ROM Drive
  • Processor
  • CPU Cooler
  • RAM
  • Video card
  • Sound card
  • Speakers
  • Floppy Drive
  • Modem

Ports

All desktop computers have ports which are used to plug external devices into the computer such as monitors, keyboards, printers and scanners.

  • USB - Used for the majority of peripherals
  • Ethernet - Used for Internet
  • Modem - Used for Internet
  • Headphone jack - Used for connecting sound devices
  • Serial - Used for connecting any device that uses a serial connector
  • Parallel - Used for connecting any device that uses a parallel connector
  • PS/2 - Used for peripherals
  • Video - Used for connecting a monitor / projector
  • Power - Used for connecting the power lead
  • Firewire/IEEE 1394 - Used for connecting external hard drives and camcorders

All-In-One

All-in-one computers are desktop computers that combine the monitor into the same case as the CPU. The original Macintosh introduced in 1984 by Apple Computer was one of the first all-in-one computers, In 1998 Apple released the iMac which was also an all-in-one computer. These types of desktop computers save desk space, but are limited when it comes to expansion to improve their capabilities. PC manufacturers have also released all-in-one computers such as Gateway.

See also

01-04-2007 01:16:19
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