Root vegetables are a nutritious, inexpensive option available throughout the year. They vary widely in characteristics, from the pungent radish to the sweet carrot. They last awhile in storage. Tubers and corms, like potatoes, are carbohydrate sources used worldwide. Examples include cassava, taro, yams and arrowroot. Qualities differ between varieties but many can be boiled, roasted or stir-fried. Regionally available options provide substitutes.