The Universal Media Disc (UMD) is an optical disc medium developed by Sony for use on the PlayStation Portable. It can hold 1.8 gigabytes of data, which can include games, movies, or music.

Unlike the Minidisc, another proprietary Sony-developed format, blank media will not be commercially available, in order to avoid piracy. However, there has been recent discussion about the UMD movie and music formats being opened by Sony, although it is not clear if this will result in the development of UMD "burners" (à la CD or DVD burners). Sony has said that it intends to keep the game-formatted UMD specifications to itself, in order to avoid competition (and presumably to profit from licensing fees).

Specifications

• Dimensions: Approx. 65 mm (W) x 64 mm (D) x 4.2 mm (H)
• Diameter: 60 mm
• Maximum Capacity: 1.80GB (Single-sided, dual layer)
• Laser wavelength: 660 nm (Red laser)
• Encryption: AES 128-bit