RetroArch is a cross-platform, sophisticated frontend for the libretro API. Developed by libretro
License: Open Source
SteamOS is a gaming-centric operating system designed for the Steam platform, focusing on modern PC games, while RetroArch is an open-source software that excels in emulating retro games across various platforms. The choice between them largely depends on whether users prefer modern gaming through Steam or retro gaming through emulation.