TempleOS is an open source, highly customisable, lightweight operating system for computers. It was created by Terry A. Davis and is designed to be a "hobbyist" operating system, with an emphasis on simplicity and ease of use. TempleOS is designed to be a multi-user, multi-tasking operating system, while still allowing an individual to use it as a single-user, single-tasking system. It features a custom-made, easy-to-use graphical user interface, and includes a wide range of applications and utilities, including a web browser, text editor, media player, and games. TempleOS also includes a range of other features, such as a custom scripting language, a built-in compiler, and network support. TempleOS is designed to be highly customisable, with users able to modify the operating system to their own requirements.
Discontinued It seems that the project is no longer updated (no release candidate since 2012, no stable release since 2008), but still fully functional.