Example sentences to accompany Indigo's answer:
Shortage: There was a food shortage during the Great Depression.
Shortcut: I don't like the way he works because he takes too many shortcuts.
Let's go this way instead, I know a shortcut.
Shortwave: Shortwave radios can be used for long distance communication. (from Wikipedia)
Shorthand: It's a good thing I can write in shorthand because the Professor speaks quickly.