All this remarkable organism needs from humans is to be placed in the ground at the appropriate season of the year, given a liberal drink of water and then left alone. Crocuses and gladioli, for example, are really corms, while such favorites as dahlias and begonias are really tubers. The differences between bulbs and corms are slight, and indeed the two look very similar. The main distinguishing trait is the method of storing food. In corms, most of the food is stored in an enlarged basal plate rather than the meaty scales, which in corms are much smaller.
Corms generally tend to be flatter in shape than round, true bulbs.
Tubers and roots are easily distinguished from bulbs and corms. They have no protective tunic and are really just enlarged stem tissue. They come in a variety of shapes, from cylindrical, to flat, to just about any combination you can imagine. Many come in clusters. Bulb has commonly come to mean any plant which has an underground food storage capacity.