Search for a basic unix tutorial. Other than that, you can list all the commands that start with any letter by typing the letter than hitting tab.
To find out about a particular command type 'man <command>'.
This will be a bit complicated for you, but learning unix takes time. Just look for tutorials and learn commands one by one.
<p>There isn't a simple list of commands that you can use as a reference, necessarily.</p><p>Terminal gives you access to a full UNIX shell using tcsh by default. Tcsh is one of many UNIX shells out there and is one of the most popular. Bash is another popular one used mostly in Linux.</p><p>Unfortunately, there aren't many, if any, UNIX books that are OS X specific; however, they are good for general reference.</p><ul><li><b>UNIX for Dummies</b> by John R. Levine and Margaret Levine Young</li>
<li><b>The Complete Idiots Guide to UNIX</b> by Bill Wagner</li><li><b>C Shell Quick Reference Guide</b> by Shirose</li></ul>