The different types of clay on a supplier's price list are separated by firing temperature first and by texture second. Get the temperature right and the body will work; get it wrong and no amount of skill saves the piece. Five families cover almost everything a pottery supplier sells.
Earthenware and stoneware, the two you will actually choose between
Earthenware fires roughly 1080 to 1180 degrees, stays porous, and is the traditional red and white low-fire family. Stoneware fires roughly 1180 to 1300, vitrifies, and is what most functional studio pottery is made from because it holds water without relying on the glaze. The kiln and the intended use decide between them, and for most people it is stoneware.
Porcelain, raku and paper clay: the specialists
Porcelain is white, high firing, translucent when thin and unforgiving to work. Raku bodies are open and heavily grogged to survive being pulled from a hot kiln. Paper clay is any of the above with cellulose fibre added for wet strength and repairability. Each exists because a general-purpose body cannot do that particular job.
Texture cuts across all of them
Within every family, suppliers sell smooth, lightly grogged and heavily grogged versions of the same body, often under the same name with a different code. Smooth throws finely and cracks more easily in thick sections; grogged builds large and is abrasive. This second axis matters as much as the family and is easier to change, because it does not affect the firing.
Reading the price list
Every supplier prints a firing range beside each body, and that range is the filter to apply before price. CTM's list groups its bodies as earthenware, stoneware, porcelain and paper clay with the range in each row; Bath Potters splits its categories by temperature in the navigation itself. Filter by range, then compare per kilogram, and the choice narrows quickly.
Questions people ask about types of clay
What are the main types of clay?
Earthenware, stoneware and porcelain by firing temperature, plus raku bodies and paper clays, which are specialist versions of the first three.
Which type should a beginner buy?
A smooth or lightly grogged stoneware, provided the kiln that will fire it reaches stoneware temperature.
Can I mix types?
Not usefully in one piece. Bodies with different shrinkage and maturing temperatures will crack apart in the drying or the firing.