An archive is a single file that contains multiple files and/or folders. Archives may be created by several different file archiving utilities and can be saved in one of several different formats. They may also be compressed to reduce the file size or encrypted for security purposes. The term "archive" can also be used as a verb, which refers to the process of creating an archive.
Archives are useful for consolidating multiple files and folders into a single file. They are commonly used for backing up data and transferring multiple files between users. For example, a Web developer may save all the HTML, CSS, and image files for a website in a single archive to share with graphic designer. By consolidating all the files in an archive, the developer only needs to send one file to the designer. If the archive is compressed, it will also take less time to transfer online.
In order to open the files in an archive, they must first be extracted from the archive. Compressed archives must also be decompressed before the files can be extracted. Both of these processes can be performed using a compatible file decompression utility, such as WinZip, StuffIt Expander, WinRAR, or 7-Zip. These programs support multiple standard archive formats, as well their own proprietary compressed file types.
Some common archive formats include Zip files, StuffIt archives, and TAR files. Zip files use a standard archive format that is supported by several file decompression programs. StuffIt archives are saved in a proprietary format that can only be opened using StuffIt Expander on Macintosh and Windows systems. TAR files are uncompressed archives that are typically created on Unix systems.