Tangible seats refer to the fixed seats in the exchange hall, and each seat is equipped with floor traders (red vests). When a member entrusts, the entrustment is entered into the matching system of the exchange through the traders on the seat; Intangible seats mean that there are no tangible seats in the trading hall of the exchange and no traders are stationed. Members directly input the entrustment into the matching system of the exchange through the computer. Opening intangible seats is convenient, fast, safe and low cost. With the development of securities and futures market and the continuous improvement of computer and communication technology, it is the general trend to replace tangible seats with intangible seats.