TAR (Tape Archive)
TAR is a Unix archiving format that bundles multiple files and directories into a single uncompressed file while preserving permissions, ownership, and timestamps. TAR is almost always paired with a compression tool (gzip, bzip2, xz) to create .tar.gz, .tar.bz2, or .tar.xz archives.
MIME Type
application/x-tar
Type
Binary
Compression
Lossless
Advantages
- + Preserves Unix permissions, ownership, symbolic links, and timestamps
- + Streaming-friendly — can be created and extracted via pipes
- + Standard on all Unix/Linux systems with no additional software
Disadvantages
- − No built-in compression — must be combined with gzip, bzip2, or xz
- − No random access — extracting one file requires reading sequentially
- − Less intuitive for Windows users than ZIP
When to Use .TAR
Use TAR (with compression) for Unix/Linux backups, source code distribution, and Docker image layers.
Technical Details
A TAR file is a sequence of 512-byte blocks. Each file entry has a header block with metadata followed by data blocks. TAR itself performs no compression — it is strictly an archival (concatenation) format.
History
TAR was created in 1979 for Unix Version 7 to write file archives to magnetic tape. The POSIX.1-2001 standard (pax format) modernized TAR with extended headers for long filenames and large files.