Two things are needed to play Emulator Games on your personal computer: an Emulator as well as a ROM.

An emulator program mimics the hardware on an old-school console. This software allows you to open and run classic games.

A ROM can be a ripped copy or the actual game disc or cartridge.

An emulator is a program which you run. The ROM, on the other hand, is the file you open. If you do that, your computer will run the old school game.
About Playstation Portable Games
Playstation Portable Rom or PPSSPP ROMs is a file with PSP games that you can run on different operating systems and experience the games of this console. These files, also called roms, require an emulator to run. The best way to run PSP games on Windows and Android is to use this console's emulator, available under the name PPSSPP.
What is Retro ROM Mean?
Retro ROMs allow you to play old video games on your modern device. These ROMs are usually in the form an emulator. This allows users to play games from older consoles on the current device.

Retro ROMs can be used for many reasons. Retro ROMs may be used by some to bring back fond memories of childhood or to play classic games they love. Some people simply love the challenge of older games that are more difficult than those today. Retro ROMs are a great way to play classic games on modern devices, no matter what reason.
Introduce GBA Roms
A file ending in" .GBA" refers to a Game Boy Advance (Game Boy Advance) ROM file. It is an exact copy or a Game Boy Advance ROM file.

If you find a GBA folder on your computer, it indicates that the game was copied directly from the read-only Memory Chip (ROM) of the console. It can be played on your PC or mobile device via an emulator just as if you were playing it on the Game Boy Advance.

Game Boy Advance ROMs files could use other file extensions, like GB or AB, but they should still work the exact same as GBA.