Archiving and Compressing: tar, gzip, zip

You will, regularly, need to bundle a folder into one file (to back it up, email it, scp it, or upload it). Linux has three relevant tools: tar bundles, gzip/xz/zstd compress, and zip does both in one cross-platform format.

tar: the standard Linux archive

tar bundles many files into one. It does not compress on its own — but it pairs with gzip/bzip2/xz/zstd to make compressed archives.

Create

# Create a gzipped tarball (.tar.gz or .tgz)
tar czvf backup.tar.gz ./project

# Create a bzip2 tarball (smaller, slower)
tar cjvf backup.tar.bz2 ./project

# Create an xz tarball (smallest, slowest)
tar cJvf backup.tar.xz ./project

# Create a zstd tarball (modern, fast + good ratio)
tar --zstd -cvf backup.tar.zst ./project

Extract

# Extract any of the above (tar auto-detects compression)
tar xvf backup.tar.gz
tar xvf backup.tar.bz2
tar xvf backup.tar.xz

# Extract to a specific directory
tar xvf backup.tar.gz -C /tmp/restore

# List contents WITHOUT extracting
tar tvf backup.tar.gz

# Extract just one file
tar xvf backup.tar.gz project/config.yaml

The flag mnemonic

c = create        x = extract       t = list
v = verbose       f = file (always required)
z = gzip          j = bzip2          J = xz

“czvf” creates verbosely, “xvf” extracts verbosely. Memorize those two.

gzip / gunzip: compress single files

gzip bigfile.log              # creates bigfile.log.gz, removes original
gzip -k bigfile.log           # keep original
gunzip bigfile.log.gz         # decompress
zcat bigfile.log.gz           # show contents without decompressing
zless bigfile.log.gz          # page through compressed file

zip / unzip: cross-platform

Use zip when sending to Windows or Mac users — they handle .zip natively without extra tools.

zip -r project.zip ./project       # zip a folder
zip secrets.zip file1 file2        # zip specific files
zip -e secret.zip file             # encrypted (prompts for password)

unzip project.zip
unzip project.zip -d /tmp          # extract to specific dir
unzip -l project.zip               # list contents

Compare formats

Format	Speed	Size	When to use
.tar.gz	Fast	OK	Default. Everyone has gzip.
.tar.xz	Slow	Smallest	Sharing big files (kernel sources).
.tar.zst	Very fast	Small	Modern systems. Best balance.
.zip	Fast	OK	Sending to Windows/Mac users.

Daily one-liners

# Backup home directory excluding caches
tar czvf home-backup.tar.gz 
  --exclude='.cache' --exclude='node_modules' 
  /home/alice

# Tar+SSH: copy a directory tree to a remote server
tar cz ./project | ssh server "tar xz -C /opt"

# Show the size of an archive's contents
tar tvf big.tar.gz | awk '{sum+=$3} END {print sum/1024/1024 " MB"}'

Common mistakes

• Forgetting f in tar — without f filename it tries to read/write to a tape drive.
• Extracting an archive that wasn’t built with a top-level folder — files spill into your current directory. Use tar tvf to check first.
• Encrypting zip with -e — the encryption is weak. Use GPG or 7zip’s AES for real security.

What to learn next

Once files are bundled, the next concern is moving them around — between directories, between machines. cp, mv, and rsync are the next stop.