One question people ask me all the time is what is the difference between yams and sweet potatoes. I think this is a great question too so I did a little research and this is what I came up with as an answer for you.
The similarity is that they are both tubers or fleshy root but they are not related at all. The confusion apparently started during slavery times when there were two main varieties of sweet potatoes. In order to differentiate between the two types slaves started calling the softer type “yams” because they were the most similar to yams found in Africa. The mis-labeling has continued to today. Here are some basic differences.