The cat command in Linux explained
The cat command prints the contents of a file. It is one of the most useful commands for anyone using a live USB drive or a fresh Linux install.
Syntax
cat file
Examples
cat /etc/os-release: shows which distribution you are runningcat a.txt b.txt > all.txt: join two files
Tip
For long files, use less so the text does not scroll past.
Keep learning
New to the terminal? Start with Linux terminal basics. You can try every command safely from a live session: see how to try Linux without installing it. Run man cat in a terminal for the full manual.
Frequently asked questions
How do I see every option for cat?
Run man cat for the full manual, or try cat --help for a short summary.
Do I need sudo to run cat?
Not for your own files. You only need sudo when the command changes something owned by the system or another user.
Is it safe to practise cat on a live USB drive?
Mostly yes, because a live session starts fresh each time. Be careful with commands that write to your internal disk, such as rm on a mounted drive or dd.