Steam is a digital distribution platform developed by Valve Corporation in 2003 for the express purpose of distributing game software, hosting multiplayer functionality, and social networking. It is similar to other digital content services such as iTunes or Google Play and is currently the world's largest digital retailer for personal computer based video games. To utilize Steam, you must have a Steam account and the Steam game client, both of which are free.
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To redeem your product keys to Steam, you can either redeem via the Steam Redemption page or follow these steps to redeem to your Steam client directly: