 to noise. The signal is coded and sent as a string of zeros and ones. Sufficiently distinct phenomena (the absence or presence of light-positive or negative voltage levels) distinguish these binary values. In digital systems, a repeater (a corollary to an amplifier in analog systems), can accurately distinguish between a zero and a one. The integrity of the signal is extremely high because, with today's transmission systems, bit errors are quite rare. Digital transmission preserves the quality of an original signal. However, that is not the only reason digital technology is SO widely accepted today. A bigger reason- the real reason- is that computers are inherently binary, or digital. They do not process analog data. To leverage the enormous power that computers can offer practically every application, one must convert sounds and pictures from their natural analog state to a digital (or binary) one. Once they have been digitized, these streams of audio and visual information can be compressed, and moved economically across telecommunications networks. AUDIO ENCODING Like conventional television, digital video consists of a series of image frames that are synchronized with an audio track. The sounds are interleaved with the video data during the process of capture and transmission. Audio and video must each be digitized. Digitizing a signal is a multi-step process that starts with sampling. Sampling is the process of measuring slices of an analog signal over time, and at regular intervals. Typically, "X" represents the number of samples taken in a second; X represents a number that is twice the highest frequency of the analog signal. In 1928, a Bell Labs engineer named Harry Nyquist presented a paper that laid out a technique for sampling an analog signal in such a way that its digital representation would be lossless-that is, functionally identical to the original waveform. Nyquist's Theorem, the gospel of digital encoding, states that the sampling rate must be twice that of the highest frequency present in the 