Yeah you kinda only need to soft mod a PSP to play dumps of PSP games on one, asides from the soft mod nothing else is needed to make a PSP run
Softmod = CWF = Custom Firmware (very easy to install)
PPSSPP is an emulator and emulators are designed to run one system on another, for this one it can run PSP system games on a Windows PC system or an Android based OS system like a phone, others you may get PSX running on an Xbox so that would be running a PSX system on an Xbox system
The PSP itself has a PSX emulator built into it as a PSX does not share the same hardware as a PSP the PSP uses software to emulate a PSX (the software is called POPS)
What an Emulator does though is translate the original hardware by software so that games or software designed for whatever system is emulated will run as they would of on real hardware (or as close as they can get it depending on any emulation issues that an emulator may or may not have, i.e. part of the emulated system may not be correctly emulated/emulated as best as possible with the given tech detail of said emulated system that may not be full)
If you want to be guided through installing PSP Custom Firmware (Software modding it) just ask but give a bit of detail about the model of PSP you own so you can be guided as best as possible
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