Unix commands: a very brief summary

Command	Action
ls	view directory contents (ls -l for a long view)
rm	remove files (rm -r to remove entire directory trees)
rmdir	remove an empty directory
cp	copy a file (cp -a to copy directory trees)
mv	move a file or directory
cat	output a file to screen
less	view a file page-by-page, with scrollback

Command help texts can be accessed with the --help switch. Directories are separated by /, not \. The root of the filesystem is /. Drive letter C: is expressed as /c/.

Environment variables in Unix

Environmental variables may be viewed with the env command. Individual variables may be viewed like this:

$ echo $PATH

and set like this:

$ PATH=$PATH:/home/<username>/bin

Sometimes variables must be exported to be visible to called programs:

$ export PATH