The Universal Media Disc (UMD) is a small compact disc manufactured by Sony that can be used on the PSP. It is the first optical disc format to be developed for a handheld video game system. Its primary function is to be a storage medium for PSP games although the format can also be used to store UMD movies. Even TV shows can now be played back on the PSP using UMD discs.

UMD videos are encoded in the MPEG-4 format. However, no other device other than the PSP can play UMD discs. As such, the market is very limited but a lot of PSP users get to enjoy watching UMD movies on their portable gadget anywhere they go.