Capcom's CPS2 system is essentially the same, a battery keeps decryption keys in RAM, used to decrypt the game so it can be played. This used to make owning CPS

Capcom's CPS2 system is essentially the same, a battery keeps decryption keys in RAM, used to decrypt the game so it can be played. This used to make owning CPS2 games a real headache, but the community has now completely nullified the issue. https://en.wikipedia.org/wiki/CP_System_II https://en.wikipedia.org/wiki/CP_System_II