ls - lists the contents of current directory
ls -l - lists the contents of a directory with permissions information and 
	timestamp
ls directoryname - lists the contents of that directory

cd - change directory.  
If you give it no arguments, it puts you back to your home, where you log in.
cd .. - go up one directory.
cd directoryname - go into a directory

mkdir - make directory
mkdir directoryname - make the new directory

rm - remove 
rm filename - remove that file
rm -i filename - a safe remove - it asks you to confirm that you want to remove 
	the file

mv - move
mv filename1 filename2 - takes filename1 and renames it filename2.  This is
used to rename a file or move a file to a different directory

cp - copy
cp /cs/faculty/franklin/labfiles/prog1/solution/* .
this copies all of the files in that solution directory to the current directory.

man - prints the man page for a function
man strcmp - this prints out the man page for strcmp, telling you what it does,
what the input parameters are, what it returns, etc.

cat - prints out a file to the screen
cat Friend.h - prints out Friend.h without having to go into vim or emacs

more - prints out a file to the screen, one screen at a time
more Friend.cpp - prints out Friend.cpp one screen at a time.  This is used for 
	a really long file so that you can look at one screen.  Press space
	bar to advance to the next screen.


./a.out | more
The pipe '|'  takes the output from your program and, instead of it displaying on 
your screen so quickly you can't read it, it prints it out one screen at a time.
The pipe makes the output of ./a.out the input for more. This can be used to 
string together any two commands (or more).

chmod - change permissions
chmod 600 filename
this makes the file readable and writable to only yourself.
chmod 700 directory
This makes the directory accessable to only yourself.
You should make sure that your directory is not accessible to any other students.