A thick walled (usu. 1/4"+) cast-iron kettle or pot used for simmering, baking, frying and slow-cooking food. The Dutch Oven was a fixture in our Boy Scout troop for use on camping trips. If you are using a Dutch Oven for baking in the outdoors (it works surprisingly well), I would recommend heating it with charcoal briquettes. Each briquette added to the bottom adds 30 deg (F), briquettes on the top add 25 deg (F). Mind you, this is not an exact measure, it depends on ambient atmospheric conditions and many other variables, but is good enough for government work.
For example, to bake a cake at 250 deg (F), place 4 briquettes on the bottom and five on the top. The briquettes must be fully burning, which is indicated by a grey ashy outer coating with cherry red hiding under the grey.

A dutch oven must be seasoned for it to heat evenly and for food not to stick to the interior. Seasoning is best accomplished by cooking fatty foods in it for fifty years or so (dutch ovens used to be passed down from generation to generation.
The one I use today was my grandmother's), but if you got a new dutch oven and don't want to have to spend 10 years breaking it in, take a paper towel and coat it in lard or Crisco and wipe the entire oven down with it until there is a thin coating of your substance of choice all over the oven (inside and out). Place this in a home oven or use briquettes to heat this to 350 deg (F) for an hour. Repeat until the oven feels slightly greasy to the touch.

***CAUTION*** if you use too much shortening or lard and are seasoning in an oven, the shortening may drip from the outside of the dutch oven, land on the heating elements and catch fire. Be sparing with your coatings.