Yam

These are the edible tubers of a tropical and subtropical plant, and the staple food of many regions, particularly South and Central America, the West Indies, Africa and the Pacific Islands. Strictly speaking, yams are the tubers of one family, but the word is often used loosely to encompass a range of other tropical roots such as sweet potato, taro and cassava. In the United States, sweet potatoes are called yams. There are many varieties, some have a coarse skin, others smooth, while some may be pale brown or purple in colour. The flesh colour also varies, from white to cream, yellow, pink or purple.