A desktop computer is a personal computer. According to the Merriam-Webster Online Dictionary, a personal computer is a a general-purpose computer equipped with a microprocessor and designed to run especially commercial software for an individual user.http://www.merriam-webster.com/dictionary/computer In 1974, the Altair microcomputer was sold for $400 as a compact computer for personal use by the technology company MITS.http://pctimeline.info/mini.htm The next year Paul Allen and Bill Gates created BASIC for the Altair system.http://pctimeline.info/mini.htm The software company Microsoft was established the same year.http://pctimeline.info/mini.htm By 1977, Steve Jobs and Steve Wozniak (of Apple Computer) are credited with marketing the first mass produced personal computer.http://pctimeline.info/mini.htm http://www.pc-history.org/

Desktop computers have a variety of uses today. They can be used for business, gaming, general purpose, video and audio editing. The kind of computer that a person needs depends on his intended use since the technical specification and prices for desktops vary widely.

The desktop built for performance is at the top of the personal computer hierarchy. These computers are used by people that need a powerful system such as gamers and 3D professionals. An example of a performance system is the following: Intel Core i7-980X processor (6 core CPU), ATI Radeon HD5870 GPU (graphics card), 2TB hard drive and 6GB of DDR3 RAM.http://www.pcworld.com/reviews/product/418480/review/cyberpower_black_pearl.html This system is around $4500.http://www.pcworld.com/reviews/product/418480/review/cyberpower_black_pearl.html

However, general purpose computers for the non-professional user have lower specifications and prices. A sample general computer could have the following specifications: AMD Athlon II processor (1 core CPU), nVidia GeForce 9200 GPU, 160GB hard drive and 2GB of DDR3 RAM.http://www.pcmag.com/article2/0,2817,2367139,00.asp This system is valued at $319.99.http://www.pcmag.com/article2/0,2817,2367139,00.asp

There are three principal operating systems for desktop computers: Microsoft Windows, Mac OS and Linux. Microsoft currently supports Windows XP, Vista and Windows 7.http://www.microsoft.com/windows/windows-7/compare/versions.aspx They can run on various machines. Apple offers Mac OS X Snow Leopard. The Mac OS only runs on Apple desktop computers.http://www.apple.com/macosx/technology/ Linux is an open source operating system, released under the GNU General Public License, that can run on any desktop.http://www.linux.org/info/

A user can find three kinds of monitors sold with computers. These are CRT, LCD and touchscreen monitors. CRT monitors are analog and use cathode ray tubes.http://bugclub.org/beginners/history/MonitorsHistory.html When buying a computer today, LCD (liquid crystal display) monitors are commonly the default add-on. LCD monitors take up less space than the CRT variety, yet some people prefer the picture quality of the CRT.http://www.pcmag.com/article2/0,2817,646212,00.asp Touchscreens allow the user to use his finger or a stylus to select items directly on the screen surface.http://www.hp.com/united-states/campaigns/touchsmart/

When picking a desktop computer, a user needs to pick a case that fits his environment. Tower cases come in three sizes: mini, mid and full.http://www.xoxide.com/buy-computer-cases.html These cases allow room for the user to add more components like extra video cards and hard drives. In contrast, a compact case is small and not built for expansion. Also, the all-in-one case is not expandable. It houses the display screen and computer hardware in one machine.