A UMD is a Universal Media Disc
You can download a DLC or add on to a game and use it to play with the UMD game
It stands for Universal Media Disc.
Put the UMD in the disc holder then press UMD under Game then play! ----
It could be the lazer that reads the disc is broken or damaged. Or the issue could be the umd itself or the firmware. I'd say send it in to sony and get it repaired. If your psp knows the umd is there but won't let you start the game the chances are the lazer is damaged or the disc is too dirty. If it lets you start the game then crashes and says the umd can't be read then could be the disc reader or the disc. First try cleaning the umd if that doesn't help then it's probably the psp. My psp 3000 has never had that but if the problem is the psp, send it in.
clean the disc or check your system
I think UMD stands for Universal Media Disc and PSP stands for Play Station Portable if that's what your asking for.
PSP UMD movies are about a lot of different things. Basically it is movies and television shows released in the United States on the Universal Media Disc (UMD) for the Playstation Portable (PSP).
The answer is both no and yes. You do not need custom firmware installed to run UMD games. UMD games are the disc-type games that you buy at the store. You will, however, require a custom firmware installed on the psp to run backups which are copies of the UMD (disc-type) on your memory stick.
try cleaning the disc
The slot on a PSP the game goes into called a Universal Media Disc a disc format created by Sony for the PlayStation Portable
nope. reads UMD (universal media disc) format.