Definition: People or firms who have memberships to a stock exchange are allowed to be on the floor to buy and sell stocks. The people you see running around buying and selling stocks are called "floor traders." These memberships can upwards of $1 million for a "seat" on the exchange.
TeenAnalyst Advice: Floor traders have high-intensity, high-risk, and high-stress jobs. They're responsible for executing all of the large orders from their firm. These aren't usually small trades, either. It's not unusual for floor brokers to buy or sell 50,000 shares at a time.