Lard is the pig's subcutaneous fatty layer, more consistent in the part attached the rind and softer in the one close to the meat; the latter is in fact melted or ground to obtain fat.
The lard is salted and sometimes smoked. For a very long time it was one of the most used fats in cooking as well as the main ingredient of the beaten recipe. Today it is used, along with bacon, to stuff meat.
