Most clay bodies that you will come into contact with are secondary clays that have been adjusted, or completely formulated clay bodies. In the formulated clays, the natural ingredients such as kaolins, ball clays, bentonites and other ingredients are mixed up to create a clay body of a particular type, e.g. a white earthenware. You can make your own clay bodies according to available recipes, experiment with your own variations or just buy a commercially manufactured clay from a potters supply shop.
Clay bodies are usually suited to certain types of work. A smooth clay which works very well on the potter's wheel may have cracking problems when we try to handbuild with it. Large sculptures are usually built with very stiff coarse clay which would be unuseable for most other purposes. The temperature to which we'll be firing our work and the fired color and texture we desire will also dictate what kind of clay body we choose to work with.