Sweet Potatoes vs. Yams

Aside from Thanksgiving, we didn't see sweet potatoes/yams in our house very often (one of the few veggies I can say that about).  I learned about their "super food" status later and after Hayden was born, I knew I wanted them to become a regular part of our diet.  But what's the difference?  Which is better?  I started buying sweet potatoes by the bag or in spears at Trader Joe's and then heard that those were actually yams, this person said sweet potatoes are white.  Confusing huh?  Especially when you see commercial baby sweet potatoes have the rich orange color you are used to seeing.  So I consulted Food Lover's Companion, my go to guide about food.

Sweet Potato:  There are many varieties of sweet potato but the two that are widely grown commercially are a pale sweet potato and the darker-skinned variety Americans erroneously call "yam" (the true yam is not related to sweet potato).  The pale sweet potato has a thin, light yellow skin and pale yellow flesh.  Its flavor is not sweet and after being cooked, pale sweet potato is dry and crumbly, much like a white baking potato.  The darker variety has a thicker, dark orange skin and a vivid orange, sweet flesh that cooks to a much moister texture... Sweet potatoes are high in vitamins A and C.

Yam: Although sweet potatoes and yams are similar in many ways and therefore often confused with one another, they are from different plant species.  In the southern United States, sweet potatoes are often called yams and to add to the confusion, canned sweet potatoes are frequently labeled yams.  True yams, however, are not widely marketed and are seldom grown in the United States.  Though they can be similar in size and shape to sweet potatoes, yams contain more natural sugar and have a higher moisture content.  On the downside, they are not as rich vitamins A and C.

So in case you were as confused as I was, that is the difference.