Valve has announced SteamOS, a free, Linux-based operating system designed for televisions and the living room.
The operating system, announced on the Steam website, will be available soon as a free download for users and as a freely licensable operating system for manufacturers.
Valve today confirmed four features for the software; PC-to-television game streaming, music and video services, Family Options, and the previously announced family game sharing.
As well as games designed natively for "living-room hardware", SteamOS users will be able to play existing Windows and Mac games on a television by running Steam on a home computer and streaming their games wirelessly over a home network.
Valve claims it has achieved "significant performance increases" in graphics processing with SteamOS, and says it is now targeting audio performance and reductions in input latency at the operating system level.
Game developers are already taking advantage of these gains as they target SteamOS for their new releases, the firm said.
Announcements will be made "in the coming weeks" regarding "AAA titles" coming natively to SteamOS in 2014.
"As we've been working on bringing Steam to the living room, we've come to the conclusion that the environment best suited to delivering value to customers is an operating system built around Steam itself," the company said in a statement.
"SteamOS combines the rock-solid architecture of Linux with a gaming experience built for the big screen. It will be available soon as a free stand-alone operating system for living room machines."
SteamOS is the first of three Steam-related announcements Valve plans to make this week. The next will arrive at 6pm BST / 1pm ET on Wednesday, September 25.
It is expected that the Half-Life 2 developer will soon reveal more news on the Steam Box hardware project - its own living-room PC designed to power SteamOS.
Speaking at Linuxcon 2013 last week, Valve boss Gabe Newell told attendees that he sees open platforms such as Linux as the future of gaming.
"None of the propriety closed platforms are going to be able to provide that grand unification between mobile, the living room, and the desktop," he said.
Newell went on to claim that this week's announcements would provide more information on hardware opportunities Valve sees "for bringing Linux into the living room and potentially pointing further down the road to how we can get it even more unified with mobile."