Searching for "PSP ISO collection" on Archive.org yields several massive, well-maintained libraries. Here are some of the most sought-after: 1. The Comprehensive "PSP-CSO-Collection"

The most common way to play PSP games today is on PC, Android, or iOS using the .

: A newer compression format that is becoming popular for its high efficiency, though it requires compatible versions of emulators like PPSSPP.