A Compact Disk is an optical storage device based on Laser technology to store digital data in the form of tiny indentations known as ‘Pits’. These indentations are encoded on a spiral track on the CD substrate using laser light and the space between successive pits is known as ‘Lands’. Originally developed for storing playback sound recordings, it is now an industry standard used for storing every type of digital data. It comes in a variety of diameters offering different storage capacities and is generally read using a 780nm wavelength semiconductor laser.
