A type of file compression used to save space for storage or transfer. Very common due to built in support in both the Mac OS and Windows OS.
Zip is a widely used file format for compression and archiving. It is natively supported across all major operating systems with built-in tools available for compressing/archiving and decompressing/unarchiving.
ZIP files generally use the file extensions
.ZIP and the MIME media type
The format is available in public domain. Apple has included built-in ZIP support in Mac OS X 10.3 (via BOMArchiveHelper, now Archive Utility) and later.