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The Steam Wiki
Steam is an online distribution by Valve Software. It is a way for them to deliver their content online, straight to the consumers. It started in 2002 as a method of patching, but became much more within the next few years. Because this process of selling and delivering online cuts out game store retailers and game publishers, Valve became involved in a legal dispute with Vivendi Universal, their publisher. Vivendi Universal argued that Valve was going against their publishing agreement.