Extended CD is the CD-Extra CD, sometimes called CD plus. Features of Optical tracks: There are two sessions, the first session is to store music, one track, one song, or piece of music, so there would be many tracks. The second session is to store data with the structure of data CD.
The above picture is the Optical track structure of CD-EX disc. As the picture shows it has two sessions. The first session has 7 Optical tracks. This indicates that 7 pieces of music has been stored on this disc. The second session is data session with only one optical track 08. The data session is set with directory, and the title of CD is "CDEX". In which, the "CD Plus" and "Pictures" is formed automatically during the burning of CE-EX. They are the structure data of CE-Extra CD.
The music can be played by CD player as the CD player can only read the first session while the computer usually read the last session.