Sometimes known as 'laserdisc'. Now largely obsolete, videodiscs are 12" analogue, laser-read devices, used primarily for the display of video material with accompanying soundtrack, but also capable of displaying still images. Videodiscs can be used on a stand-alone basis or connected to a computer to permit what used to be called 'interactive video'. A videodisc can store 36 minutes of video and stereo audio per side or more than 50,000 still frames.