PlayStation Network, PSN for short is the network for the PlayStation 3 and PlayStation 4 created and owned by Sony. It contains several features, most notably the PlayStation Store, where one can download games, demos and game expansions. As for Ratchet & Clank, there is not much to it yet. You can play the multiplayer of All 4 One, use online profiles in A Crack in Time, and share trophies earned in these two games with other PSN players. You can also play the multiplayer from Up Your Arsenal in Ratchet & Clank Collection and play the multiplayer from Ratchet: Deadlocked as well.