Compression, bit rate reduction and data reduction are all terms which mean basically the same thing in this context. In essence the same (or nearly the same) information is carried using a smaller quantity or rate of data. It should be pointed out that, in audio, compression traditionally means a process in which the dynamic range of the sound is reduced. Provided the context is clear, the two meanings can co-exist without a great deal of confusion.
There are several reasons why compression techniques are popular:
(a)Compression extends the playing time of storage devices such as file servers.
(b)Compression allows miniaturization. With less data to store, the same playing time is obtained with ...