untar

Untar is the process of extracting files from a tar archive. Tar, short for tape archive, is a container format used to bundle multiple files into a single archive, originally to simplify storage on magnetic tapes. Tar archives can be uncompressed or compressed with gzip, bzip2, or xz.

In Unix-like systems, the tar command performs extraction. The basic syntax is tar -xvf archive.tar, where -x extracts, -v lists files, and -f specifies the archive file. For compressed archives, common variants are tar -xzvf archive.tar.gz (gzip), tar -xjvf archive.tar.bz2 (bzip2), and tar -xJvf archive.tar.xz (xz). A destination directory can be chosen with -C.

On Windows or other platforms, untar can be done with utilities such as 7-Zip, WinRAR, or via Windows Subsystem for Linux, which provides a tar implementation. Some tools allow extracting without verbose output or with more advanced options.

Security considerations include avoiding extraction of archives from untrusted sources, as archives may contain files with absolute paths or dangerous symlinks. Use --strip-components to remove leading directories and extract into a dedicated directory, and verify checksums when provided.