At various times, PKWARE has added preliminary features that allow PKZIP products to extract archives using advanced features, but PKZIP products that create such archives are not made available until the next major release. ZIP File Format Specification has its own version number, which does not necessarily correspond to the version numbers for the PKZIP tool, especially with PKZIP 6 or later. PKWARE and Infinity Design Concepts made a joint press release on February 14, 1989, releasing the. By distributing the zip file format within APPNOTE.TXT, compatibility with the zip file format proliferated widely on the public Internet during the 1990s. ZIP File Format Specification was first published as part of PKZIP 0.9 package under the file APPNOTE.TXT in 1989. They wanted to imply that their product would be faster than ARC and other compression formats of the time. The name 'zip' (meaning 'move at high speed') was suggested by Katz's friend, Robert Mahoney. The format was created after Systems Enhancement Associates (SEA) filed a lawsuit against PKWARE claiming that the latter's archiving products, named PKARC, were derivatives of SEA's ARC archiving system. ZIP file format was designed by Phil Katz of PKWARE and Gary Conway of Infinity Design Concepts.

When navigating a file system via a user interface, graphical icons representing ZIP files often appear as a document or other object prominently featuring a zipper. ZIP is used as a base file format by many programs, usually under a different name. ZIP and the MIME media type application/zip. ZIP files generally use the file extensions. Most free operating systems have built in support for ZIP in similar manners to Windows and Mac OS X. Apple has included built-in ZIP support in Mac OS X 10.3 (via BOMArchiveHelper, now Archive Utility) and later. Native support was added as of the year 2000 in Windows ME. Microsoft has included built-in ZIP support (under the name 'compressed folders') in versions of Microsoft Windows since 1998 via the 'Plus! 98' addon for Windows 98. The ZIP format was then quickly supported by many software utilities other than PKZIP. This format was originally created in 1989 and was first implemented in PKWARE, Inc.'s PKZIP utility, as a replacement for the previous ARC compression format by Thom Henderson. The ZIP file format permits a number of compression algorithms, though DEFLATE is the most common.

A ZIP file may contain one or more files or directories that may have been compressed. ZIP is an archive file format that supports lossless data compression.

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