A series of techniques used for the reduction of space, bandwidth, cost, transmission, generating time, and the storage of data.These techniques are designed to eliminate repetition, remove irrelevances, and employ special coding techniques.

• 在减少空间和时间消耗、缩小频带宽度、压缩存储量和传输量、降低成本等方面采用的一系列技术。如消除重复、去掉无关项、使用特殊编码技术等。