Compact discs (CDs), MP3s, and Digital Versatile Discs (DVDs) are currently some of the most popular ways to enjoy music and movies. Utilizing the latest in digital technology they have each been able to improve on the standards set by their predecessors.

A finished compact disc contains a series of tracks or indentations called "lands" and "pits." A CD player uses a laser beam to read these layers and convert the reflection first into an electrical signal and then into music.

Compact Discs

A compact disc is a storage medium with digital data recorded on its surface. An optical beam reads the CD and reproduces the sound. Because the beam does not touch the CD, there is no wear and tear on the disc.

Compact discs store sound through a process known as Pulse Code Modulation (PCM...