bash
ShellPackage: bash
The default interactive shell of human accounts on Ubuntu, and the interpreter of most administration scripts. bash -n checks a script's syntax without running it; bash -x shows each command as it runs.
What its options do in the lessons
From the same glossary the lessons render under their commands, so the two cannot disagree.
bash -n- Reads the script and reports syntax errors without running it.
bash -x- Prints each command before running it — the most direct way to see what a script really does.