Reduces storage space and hence storage cost.
Reduces time to retrieve and transmit data.
compressedData = compress(originalData)
decompressedData = decompress(compressedData)
When originalData = decompressedData
the compression is lossless
When originalData != decompressedData
the compression is lossy
Lossy compressors generally obtain much higher compression ratios than do lossless compressors.
Lossless compression is essential in applications such as text file compression.
By Chaker ben hamed
