Optical media – such as the compact disk (CD) – are storage media that hold content in digital form and that are written and read by a laser; these media include all the various CD and DVD variations, as well as optical jukeboxes and autochangers. Optical media have a number of advantages over magnetic media such as the floppy disk. Optical disk capacity ranges up to 6 gigabytes; that’s 6 billion bytes compared to the 1.44 megabytes (MB) – 1,440,000 bytes – of the floppy. One optical disk holds about the equivalent of 500 floppies worth of data. Durability is another feature of optical media; they last up to seven times as long as traditional storage media.