This is a universal lossless data compression algorithm designed by A. Lampel, Jacab Ziv, and Terry Welch, which was published by T. Welch in 1984 as an enhanced version of LZ78 algorithm. Lempel Ziv algorithm is mostly used in compression like gzip, GIF, and V.42 modem standard. There are two algorithms derived from Lempel Ziv algorithms , they are LZ77 and LZ78.
Most data carry a pattern, for instance in an article some letters appear more often than others, data compression techniques uses this method to compress data by replacing repeated letters by adding different short value to it and get a small size than the original data. Reproducing the original data is possible in this lossless data compression method. Lempel Ziv uses an adaptive dictionary; this is created in while the data being encoded. On the other hand it is not required to transmit or store the dictionary since decoder is capable of building the dictionary. The dictionary size can increase infinitely large in theory, although it practice it increased to certain extend and stop. Recommended size of a dictionary is 4096.
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