pwd	What directory am I currently in?
ls	short list of this directory's contents
ls -l	detailed list of this directory's contents including permissions
ls -l  |  more	detailed list of this directory's contents, served up one screenful at a time;     (hit the space bar to see the next screenful)
cd public_html	go down a level to my public_html subdirectory
cd	go to my home directory
cd ..	go up a level, to the parent of the current directory
mkdir proj1	create a new subdirectory under the current directory called proj1
chmod 755 proj1	make proj1 readable and executable (but not writable!) for everybody
cp file1 newfile	make a copy of file1 called newfile
cp file1 ../proj2/newfile	make a copy of file1 called newfile in the parallel subdirectory proj2
rm file1	remove (delete) file1
rm file?	remove all the files file1, file2 ... (? is wildcard for any one character)
rm *	remove everything in this directory! (* is wildcard for any number of characters)
rm *.png	remove everything with a name ending in .png in this directory
rmdir subdir2	remove subdirectory subdir2 (must be empty)
mv file1 newname	rename file1 as newname
mv file1 subdir3	move file1 to the subdirectory subdir3     (if subdir3 doesn't exist, file1 will be renamed subdir3!)
clear	clears the SSH window (good idea after a Pico edit session)
quota -v	tell me how much of my disk quota I have used