This picture was taken in 1920, and shows Curb Brokers on Wall Street in New York City. Up until 1929, the American Stock Exchange was known as the New York Curb Exchange. This is because brokers would meet outside, on the curb, with lists of stock for sale, or that were wanted. It became so crowded, popular, and loud, that hand signals had to be introduced as a means of communication between buyers and sellers. The exchange moved indoors in 1921.