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.
[citation needed] Blu-ray discs can also be written in a sequential, session based mode modelled on CD and DVD.
Extra content and bonus features on a DVD are also on separate tracks or titles.
One such extension, the Yellow Book, defines the CD-ROM specification -- a standardized method of storing arbitrary digital data in a CD track.
As such, the apparent randomness of encoded sample values tends to manifest as white noise, similar to the static of an untuned analog TV or radio receiver.
Consequently, many CD players manufactured from the late 1990s onwards will mute the audio output when they detect a data track.
[2] The following table shows the structure of a multi-session CD: In sequential Blu-ray discs, session ranges are recorded in a "Sequential Recording Range Information" (SRRI) field of a "Disc Management Area" (DMA).
[1]: 36 When a disc is finalized or closed, the latest information in the temporary DMAs such as SRRI is taken and copied into the DMA.