- Not to be confused with Zip disk, an unrelated disk cartridge unit.
ZIP is one of the most popular file compression formats. It was created in 1989 as the native format of the PKZIP program, which was introduced by Phil Katz in the wake of a lawsuit (which he lost) against him by the makers of the then-popular ARC program (and file format) for copyright and trademark infringement in an earlier program PKARC which had been file-compatible with ARC. This resulted in Katz creating a new file format, which rapidly overtook ARC in popularity (to a large extent because of BBS sysops, then the primary users of such compression, resenting the lawsuit). Many programs have been released for a variety of operating systems to compress and decompress ZIP files, and native support for the format is built into several popular operating systems.