One of my friends in college i noticed was always playing retro games on his laptop, with a usb powered joypad, which basically transfored his laptop into a retro games console.
Sonic, Streets of Rage, Super Mario Brothers etc.. were all being played and i couldn’t help but get lured into them and rekindling all of the memories i had as a child playing those games.
These are real arcade style games… the all time classics which can never be beaten in many ways. Anyway, i found out he was using an ’emulator’ to act as the ‘games console’ and ‘roms’ to act as ‘games’.
So basically you download an emulator, then individual roms. That then fools your PC into thinking it’s a sega megadrive or nintendo etc..