Steam Steam is a video game digital distribution service and storefront by Valve. It was launched as a software client in September 2003 as a way for Valve to provide automatic updates for their games, and expanded to distributing and offering third-party game publishers' titles in late 2005. Valve 2003 2003-09-12 September 12, 2003 Folder 3-4 215D90 2F3B50 0A7CAF EEEEEE 2A2E33 Mapp