Piano Teacher/ Players What do you call the thing that helps you keep your beat as you play piano?

I've seen those things that, are like a drum beat, and you can set the speed of your play, so you can keep a beat with your notes. What are they called and where can I get one. My piano keyboard has one on it. But I want a manual one. Where can i get it and what is it called.

A Metronome.

http://en.wikipedia.org/wiki/Metronome

http://www.metronomeonline.com/