Zip is a common type of file compression. "Zipping" one or more files creates a compressed archive that takes up less disk space than the uncompressed version. It is useful for backing up files and reducing the size of data transferred over the Internet.

An archive compressed with standard Zip compression has a .ZIP file extension — for example, To open the file or files in a Zip archive, you must first "unzip" or decompress the archive. Both Windows and macOS include a built-in file decompression utility that can unzip Zip files. Alternatively, you can use a third-party file archiving application, such as WinZip or 7-Zip, to decompress a Zip file.

Zip Compression Ratio

How much a file can be compressed depends on the original data. For example, a plain text file can be compressed much more than a JPEG image file, since JPEG data is already compressed. Zipping a text file might generate an archive that is only 25% of the original file size, while a zipped JPEG file may still be 95% of its original size.

NOTE: "Zip" also refers to a removable storage device made by Iomega during the 1990s and early 2000s. The original Zip drive supported 100 megabyte removable Zip disks — significantly more than the 1.44 MB floppy disk alternative. Later models supported 250 and 750 MB disks. The popularity of Zip disks faded as hard drive costs declined and the storage capacity of portable flash drives increased.

File extensions: .ZIP, .ZIPX

Updated September 30, 2019 by Per C.

quizTest Your Knowledge

Errors in computer code are collectively called what?

Correct! Incorrect!     View the Bug definition.
More Quizzes →

The Tech Terms Computer Dictionary

The definition of Zip on this page is an original definition written by the team. If you would like to reference this page or cite this definition, please use the green citation links above.

The goal of is to explain computer terminology in a way that is easy to understand. We strive for simplicity and accuracy with every definition we publish. If you have feedback about this definition or would like to suggest a new technical term, please contact us.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe or change your frequency setting at any time using the links available in each email.

Questions? Please contact us.