Strange issue: Disappearing Dock

I just had a goofy problem. I'm sure it's been solved in the forum before, but a casual search for the word "dock" brings up too many diverse threads. My dock disappeared! When I drug my mouse down to the bottom of the screen, my dock didn't fade up like it normally does. A restart solved it. I guess the dock app just stopped responding. Is there a trick to fixing this if it happens again (though, I've never encountered it before).

Open the program "Terminal" (Applications>Utilities) and type:

killall Dock

Then press Return. This resets the application.

Most likely the Dock just crashed. It happens from time to time.