In the U.S., you’ll often find grocers interchanging the two names. But, you’ll find that Sweet Potatoes and Yams, while similar in appearance, taste different. In fact, most likely the “yams” you’re getting at the market are just Sweet Potatoes. The copper color skinned ones are often referred to as a Yam or a Sweet Potato Yam. However, they’re usually just a firmer Sweet Potato. The softer Sweet Potatoes are usually yellow inside and have lighter skin. True Yams are native to Africa and Asia. They grow as a root vegetable to a flowering plant and cook differently than Sweet Potatoes. Yams have brown, bark-like skin and aren’t commonly found in US markets.  You would need to check out a special grocer and they may not taste as sweet in this Southern Candied Sweet Potatoes dish as regular Sweet Potatoes would.