A year earlier, Philips had already produced a prototype for compact disc player in Europe. Since then, the technology for compact discs and their players have greatly evolved. CD technology has greatly revolutionized the idea of a spinning disc. In the mid-20th Century, people were using turntables to spin records at 45 revolutions per minute. CDs spin at an angular speed of 500 rpm when read from the center and 200 rpm when read near the circumference.
Records contain grooves that have been coded with amplitudes that correspond to a specific sound.
The spaces between the pits are a digital representation of the recorded sound. The information on these pits is read by lasers that do not physically touch the disc as in a record. By using a digital representation of the sound, the physical wear of recording and playback is greatly reduced. The sound quality is far much better than analog systems. CDs are not only used in the music industry, but are also utilized in the computer industry.