Is a yam the same as a potato?

Potatoes and Yams are quite different from one another. While both are edible tubers, they are markedly different in texture, flavour and cooking times. To confuse the subject further, the word yam is used to refer quite different families of tubers. In most of the world, Yam is the common name for group of tubers native to Africa and Asia. In the southern parts of the United States the word is used to refer to a group of tubers native to South America - which are called sweet potatoes elsewhere.