stands for Universal Media Disc , the proprietary optical disc format Sony used for PSP games and movies. When you rip a physical UMD game to your computer, you typically end up with an .iso or .cso file. However, many modern PSP emulators (like PPSSPP) and custom firmware installations require an additional layer of metadata to run certain games correctly.
Verify File Size: These files are often several hundred megabytes; be wary of tiny files. umd data.bin download