Track (optical disc) Track (optical disc) On an optical disc, a track (CD) or title (DVD) is a subdivision of its content. Specifically, it is a consecutive set of "sectors" (called "timecode frames" on audio tracks) on the disc containing a block of data. One "session" may contain one or more tracks of the same or different types. There are several kinds of tracks, and there is also a sub-track index for finding points within a track. Blu-ray discs can also be written in a sequential, session based mode modelled on CD and DVD. A Blu-ray "track" refer to the entire physical storage
Optical disc current third-generation discs and have the potential to hold more than one terabyte (1 TB) of data and meant for distributing Ultra HD video : There are numerous formats of optical direct to disk recording devices on the market, all of which are based on using a laser to change the reflectivity of the digital recording medium in order to duplicate the effects of the pits and lands created when a commercial optical disc is pressed. Formats such as CD-R and DVD-R are "Write once read many", while CD-RW and DVD-RW are rewritable, more like a magnetic recording hard disk