Then, he clicked
Using a free tool called imgburn , Leo created a complete, 1:1 copy of the disc—a . It was 4.3 GB of raw data: the game’s code, its music, its voice acting, and its unique boot sequence. An ISO is just a digital ghost of the physical disc.
Clever homebrew developers had extracted that emulator and built tools to let you wrap your own ISOs in the same way.