A barker is a person who stands outside a circus, carnival, or show and loudly calls out to passersby, trying to convince them to come inside and buy a ticket. Barkers would shout about the amazing acts, the death-defying stunts, or the incredible curiosities waiting inside: “Step right up! See the strongest man in the world! Only ten cents!”

Before radio and television, barkers were a carnival's main form of advertising. They needed strong voices, quick wit, and a talent for making everything sound thrilling. A good barker could describe a simple magic trick in a way that made it sound like the most astonishing thing you'd ever see.

The job got its name because these showmen would bark their announcements like a dog barks: loud and insistent, competing with all the other noise and activity of a busy fairground. While traditional barkers have mostly disappeared, you might still hear the term used for anyone who aggressively promotes something, like a barker trying to get tourists into a restaurant or shop. The image of the old-time carnival barker, with his striped jacket and booming voice, has become a classic piece of American entertainment history.