AT, compression> A compressionstandard derived from LZ77 it is reportedly used in zip, gzip, PKZIP, and png, among others. Unlike LZW, deflATe compression does not use pATented compression algorithms. Used as a verb to mean to compress (not decompress!) a file which has been compressed using deflATe compression. The opposite, inflATe, means to decompress dATa which has been deflATed. DeflATe is described in RFC 1951. (1997-06-21)