The Gzip (Deflate) algorithm is one variant of the LZ1 (Lempel-Ziv 1) class of lossless data compression algorithms. Like other LZ1 algorithms such as ALDC, Gzip operates by searching for matches of the current input data against previously observed data. When a match is located, the position of the match in the history buffer and the length of the match are used for its output. The decompressor (Inflate) keeps an identical history buffer and is thus able to exactly reconstruct the original sequence. The Gzip/Deflate algorithm has been in the public domain since its first release in 1991, and is used in many applications including archival, point-to-point compression, and dynamic web page compression. Information on the Gzip/Deflate algorithm is available at www.gzip.org.