When you walk into a crowded bar, the sound may not be apparent at first. But before long, your ears will pick up the rhythm of an unmistakable beat.
It's a bartender's shake.
"Some people think I'm listening to a rumba when I'm shaking," says D.C. bartender Eddie Kim. "I don't think it matters what the background music is as long as you keep a rhythm."
Another Beltway bartender, J.P. Fetherston, agrees, adding that the spectacle helps him keep his audience captivated.