As early as in the Song Dynasty, "takeout" services were already available. In Zhang Zeduan's popular painting Riverside Scene at Qingming Festival, there is a restaurant boy who has just come out of the shop with "to-go boxes" in his left hand and tableware ( 餐 具 ) in his right, still (wear) the shop apron and seeming to deliver the food somewhere. That image(believe) to be a reflection of the original takeaway boy. In ancient times, there were three ways to order food. The first is servant order. Send a family retainer ( 仆人 ) to go to a restauranthe can make an order. When the food is ready, there is someone who (particular) delivers the food to the customer's home, and then gets paid. The second is agreed delivery. Sign a long-term(agree) with the restaurant. The store,every agreed day, will pack the food well and send it to the customer's home. The last one is door-to-door selling. The sellers from restaurants sell the food door to door, especially in the entertainment places like theatres, are crowded with many people. The to-go box, wenpan (warm tray), (consist) of two layers of porcelain( 瓷 ). When (use), hot water is injected into the interlayer of the plate (keep) the dishes warm. In this way, the dish is still warm when it arrives at the customer's home.