Physical Organization of CD-ROM I
CD-ROM is a descendent of CD Audios. i.e., listening to music is sequential and does not require fast random access to data.
Reading Pits and Lands: CD-ROMs are stamped from a glass master disk which has a coating that is changed by the laser beam. When the coating is developed, the areas hit by the laser beam turn into pits along the track followed by the beam. The smooth unchanged areas between the pits are called lands.