Homebuilt computer

A custom-built or homebuilt computer is a computer assembled from available components, usually commercial off-the-shelf (COTS) components, rather than purchased as a complete system from a computer system supplier, also known as pre-built systems.

Homebuilt computers are almost always used at home, like home computers, but home computers were traditionally purchased already assembled by the manufacturer. However, there were kits that were both home computers and homebuilt computers, like the Newbear 77-68, which the owner was expected to assemble and use in his or her home.

Computers have been built at home for a long time, starting with the Victorian era pioneer Charles Babbage in the 1820s. A century later, Konrad Zuse built his own machine when electromechanical relay technology was widely available. In 1965 electronics engineer James Sutherland started building a computer out of surplus parts from his job at Westinghouse. The hobby really took off with the early development of microprocessors, and since then many enthusiasts have constructed their own computers.

Early examples include the Altair 8800 from the United States and the later British Newbear 77-68 and Nascom designs from the late 70's and early 80's. Some were made from kits of components, or simply distributed as board designs like the Ferguson Big Board. The Altair 8800 pioneered the S-100 bus which somewhat simplified the process. Ultimately, the development of home computers, the IBM PC (and its derivatives and clones), and the industry of specialized component suppliers that grew up around this market in the mid 80's have made building computers much easier. Computer building is no longer limited to specialists. Computers based on Apple Macintosh and Amiga computer platforms often can not be built in general by users legally because of patents and licenses for their hardware, firmware, and software.

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