Shell Scripts

Q. Shell scripts.. Simultaneously when I was learning Applescripts, i've learned shell scripts. This is what I know so far
A.

1. ls - directory listing
2. cd .. - same as windows but with a space before the double dots
   
3. man - gives the manual for any command ex: man ls
   
4. clear -
   
5. top - shows what programs are running
   
6. [ ] means anything optional
7. ./file - this runs the file in the current directory instead of something in the path
8. chmod +x file - makes the file an executable
9. vi - is some sort of editor with a complex set of commands