Chapter 4. How Digital Television Works
Analog television broadcasts transmit programming in a continuous signal that varies in amplitude, depending on the information contained in the picture. This signal can easily deteriorate or suffer interference from other sources, which produces a lower–quality picture than the original.
A digital broadcast, in contrast, converts the programming into a stream of binary on/off bits—sequences of 0s and 1s. Each bit represents a small part of the picture, and all the bits combine to reproduce a picture identical to the original.
The primary advantage of digital broadcasting is that these binary bits recombine ...