It is a heavy, round cast iron pot with a handle and an iron lid that has a half inch lip all the way around the edge. One variation looks like a large frying pan with four legs. It is often called an Old Time Oven or an Old Bread Oven.
The Dutch Oven can be used outdoors or inside by the fireplace. It is placed on hot coals raked directly onto the hearth. The lid and oven are preheated before using. Preheat the oven on the coals themselves and the lid directly on the fire. When the oven and lid are hot enough, the bread dough (or whatever else is to be baked) is poured into the Oven and the lid is set on top with a pair of tongs. Coals can be piled on top of the lid for additional heat. The lip around its edge keeps them from rolling off. One must be careful that the coals under the oven are not too hot or the food may burn. The lid can be much hotter than the bottom as it does not touch what is being baked.
Dutch Ovens are usually use for baking bread and biscuits. But can also be used to bake cakes, roast potatoes and meat, and heating up stews and soups.