Beet, Beetroot or Red Beet are related to chard. Sugar beet is an important beet crop for making beet-based sugars, while mangold (manglewurzle) is used a cattle fodder. Beetroot is the base for the classic Russian soup, borsch. Beetroot is used a lot for salads, generally pickled, but is also a good vegetable for baking and then eaten as a vegetable. In the USA, small beets are served as Yale beets and in a sweet and sour sauce as Harvard beets.
Dowell, P., Bailey, A. (1980) The Book of Ingredients, Dorling Kindersley. ISBN 0718119150.