The terms sweet potato and yam are often used interchangeably. The fact is they are similar, but different root vegetables. Sweet potatoes are typically what we see in local grocery stores. Orange skin, with a sweet and moist pulp, once cooked. They come in several varieties, the most common with orange pulp, but you can also find them with white or purple. Yams have brown, rough skin and are generally more firm and starchy. Yams are more compatible with regular potatoes. While you may be able to find yams in your local grocery store, they are more readily available in international markets.