All new games for PS3
It depends on the game type. Disc-based games have an "install" option which puts game data on the hard drive, but still requires the game disc to launch the game. All this "installation" does is shorten loading times by getting the information from the hard drive.
PlayStation Network (Store) games are different, however. They are usually purchased/downloaded from the PlayStation Store and are then installed onto the hard drive. You will then have an icon that depicts the installed games you have under your trophies or loaded game disc on your CrossMediaBar. These games do not require any disc to be launched and some will support from-Home launching in the future.
PSOne games are yet another type of game you can install. Purchased in the same way you would purchase PS Network (Store) games, these games can be launched directly from the CrossMediaBar. They can also be transferred to an activated PSP system for portable use.
The final game type is PSP-only games. These games are purchased/downloaded from the PS Network (Store) once again, but cannot be launched by the PS3. You must connect an activated PSP system and activate the game in your CrossMediaBar in order to transfer the game from your PS3 system to the PSP.
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