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Compression

Compression
To reduce in size. The amount of storage space required to store data can be reduced if the data is compressed.

Compression can be achieved either without loss of information (called "lossless") or may result in some loss of information (called "lossy").

Lossy compression algorithms typically allow a choice between low compression and low data loss or high compression with correspondingly higher data loss. Lossy compression is used where some data loss can be tolerated and is typically used for images, for example .jpeg and .mpeg files contain images compressed with a lossy image compression technique.

Lossless compression is used for compressing where no data loss can be tolerated, for example when compressing applications or application data. For example, .zip files use a loss-less data compression technique, similarly .tif files are a popular loss-less compressed image file format.