Yam, also known as yam, is the product name of yam (scientific name: Dioscorea opposita). It is the root tuber of Dioscorea zingiberensis, a perennial herbaceous plant in the Dioscoreaceae family. It is excavated in winter. It grows in areas between 350 meters and 1,100 meters above sea level. It grows mostly in hillsides, valleys, under forests, roadside shrubs, streams, and weeds. Yam is easy to cultivate and is most suitable for growing in yellow sandy soil. China has a history of cultivating yam for hundreds of years. It is widely distributed, and the famous places are Henan, Fujian, Shandong, Hebei and other places. Rich in nutrition and high medicinal value.