What Does PSN Mean When Purchasing A Game?

It stands for PlayStation Network and it means that the game is specifically made for digital distribution and purchase only. So they're only available digitally. You initially won't find them in retail, unless it's some re-release or something like that. Like The Witness and Sportfriends, these are typically smaller games meant to be download-only. It -confusingly- has nothing to do with PlayStation Now.

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