This page covers the history of operating system development as it applies to educational, amateur, and smaller operating sytemssystems. For a general overview of the history of mainstream OSes [[Wikipedia:History_of_operating_systems]] may be consulted. For a detailed timelinetime-line and hierarchy of Unix and similar OSes a good source of information is [http://www.levenez.com/unix/ http://www.levenez.com/unix/].
Informal operating system development([[OS Development|OSDev]]) has become a growninggrowing hobby and pasttimepast-time in the last several years. While many developer that frequent [http://www.osdev.org http://www.osdev.org]] are involved in a college level computer degree project more still seem consider osdev'ing a enjoyable pasttimepast-time. The upswing in os development may be connected to the availability of hardware documentation that the internetInternet has helped provide. Also possibly a factor is the popularity of Linux. Linux was not the first operating system that provided it's source code but it is arguably the most popular. Since may people are aware that Linux is open source they are more inclidedinclined to look at how an OS functions. Linux itself was created after it's original author, Linus Torvalds, viewed the source code for Andrew Tannenbaum's MinuxMinix OS. Linux has become large enough that it is now a large commercial project with several companies providing large amounts of investment. While Linux can be considered commercial today it wasn't originally, to quote a 1991 newsgroup posting from Linus ''Hello everybody out there using minixMinix - I'm doing a (free) operating system (just a hobby, won't be big and professional like gnu) for 386(486) AT clones.''.
