TAR file format

In computing, tar is a type of file format: the Tape ARchive format. It is used almost exclusively in the UNIX world. tar does not support compression, but it used to accumulate a large collection of files into a single archive, while preserving filesystem information such as user/group, permissions, date, directory structure, etc.

It is most commonly used in tandem with an external compression utility such as zcat, gzip, bzip2, or, formerly, compress.

A tar file that is subsequently compressed using gzip is often called a TGZ file.