Essentials of Discrete Mathematics, 2nd Edition

Chapter 6Thinking ThroughApplications

In the 1970s, music came on vinyl. The best way to get high-fidelity recordings of your favorite tunes was to invest in a good turntable and buy the LP—the “long playing” (33⅓-rpm) record. The grooves in an LP are a copy of the vibrations of the recorded sound; the turntable needle vibrates as it runs over these rising and falling grooves, and these vibrations are amplified and transmitted to the speakers, whose diaphragms vibrate to produce the desired sound waves. This method of recording is called analog because the form of the recording medium (the LP) is analogous to the form of the data (the sound waves). The grooves in an LP are continuous and relatively smooth; their shape matches the changes in ...