Which gaming company first introduced a successful digital distribution platform that fundamentally changed game retail from physical to digital sales?

The gaming industry has undergone significant retail transformations in recent years. Physical game stores have given way to digital distribution platforms, subscription services, and virtual marketplaces. This transformation has changed not only how games are sold but also how they're marketed, distributed, and consumed. Test your knowledge about a pivotal retail innovation that changed the gaming landscape forever!

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Valve (with Steam) in 2003
Microsoft (with Xbox Live Marketplace) in 2005
Sony (with PlayStation Store) in 2006
Apple (with App Store) in 2008