Three strings walk into a bar

Three strings walk into a bar. The bartender throws them out, yelling “Can’t you read the sign?! I don’t serve strings.” The strings try again, and again the bartender kicks them out. Finally, one of the strings gets the idea to mess himself up a little. He walks into the bar. The bartender scowls, “What’s wrong with you? Can’t you read? I don’t serve strings!” The string replies, “I’m a frayed knot!”