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About Steam
Steam

Steam is developed by US based developer and digital publisher Valve (Half Life 1+2, Counterstrike, Left4Dead) and was one of the first download and publishing platforms.
After a somewhat shaky start - we all remember the big discussions around the forced distribution of the local Steam client with Half Life 2 - it developed into the market leading provider of digital games. As of some unconfirmed statements it is said to hold up to 70% of the games download market!
In addition to the download and publishing aspects the Steam platform pioneered a number of features like automatic patch handling, a seamless installation, achievements and community features. However, to use all this exiting stuff you need to install and run a local client that comes with its own benefits and drawbacks. Still, Steam offers one of the most comprehensive and streamlined online shopping experiences for download games on the web.

Find this shop at: http://www.steampowered.com
All Current Game Download Deals from Steam