How to shutdown computer with Timer

How to shutdown computer with Timer: "Here is another trick to shutdown at a specific time, for example you wish to shutdown at 3:45am then do this….
Type this in
start=>Run
TYPE Code: at 3:45 shutdown -s
[Time should put when you want to shutdown your pc]
TO ABORT TIMER:
Type Code: shutdown -a
done

you can play with your friends with this…"