TAR
Also known as: .tar file, tarball, how to open tar
TAR (tape archive) bundles many files and folders into one .tar file but does not compress them on its own. It is almost always paired with a compressor, producing combinations like tar.gz (gzip) or tar.xz.
- Bundles files but does not compress by itself
- Usually paired as tar.gz, tar.bz2, or tar.xz
- Preserves Unix permissions and structure
Bundle now, compress separately
A plain .tar just concatenates files into a single archive while preserving Unix permissions and folder structure — so a 100 MB folder becomes a ~100 MB tarball, with no space saved. That is by design: TAR handles bundling, and a separate tool handles compression.
That is why you constantly see double extensions like .tar.gz, .tar.bz2, or .tar.xz (often shortened to .tgz). The .tar is the bundle; the second part is the compressor that shrank it.
TAR vs tar.gz
If you only need to keep files together, a bare .tar is fine. If you also want to save storage or speed up a download, compress it into a tar.gz or tar.xz — that single step is what actually reduces the size.
Extract on Mac or Linux with `tar -xf archive.tar.gz`, or on Windows with 7-Zip or the built-in `tar` command. Extraction writes full-size copies, so you can delete the tarball afterward.