A CD changer has a cartridge which holds all the CDs. Some CD changers are multiple whereas others hold single CDs. A multiple CD changer enables a person to access any of the CDs inside the changer either through a remote or manually. An internal CD changer works the same as an external CD changer. However, the main difference is that the cartridge in an internal CD changer does not leave the CD player. It accepts multiple CDs and stores them internally. There is some kind of a platter inside which can hold 3, 5 or 7 CDS at a time. When the "change" button is pressed on the remote or the key board that is attached to the CD player, the cartridge moves the platter around to determine the disc that is supposed to be played.
