SteamOS is a Arch Linux based Linux distribution designed to run Valve's Steam and Steam games. It also provides a desktop mode KDE Plasma which can run regular Linux applications. In addition to an Arch Linux base, SteamOS features various third-party drivers and updated graphics stack, a newer Linux kernel with long-term support, and a custom graphics compositor designed to provide a seamless transition between Steam, its games and the SteamOS system overlay. The base operating system is open-source software, but the Steam client is proprietary.