Paszlib is a Pascal port of zlib, a lossless data compression library. The zlib data format is portable across platforms. Unlike the LZW compression method used in Unix compress, the compression method currently used in zlib essentially never expands the data. zlib's memory footprint is also independent of the input data and can be reduced, if necessary, at some cost in compression.The compression algorithm used in zlib is essentially the same as that found in gzip and Zip. An unzip library is included in zlib which can extract files from ZIP archives. A Windows DLL version of zlib can be created from this source code.