Ham is a pig's hind leg, first cut off the carcass and then smoked, salted or dried (or a combination of these) for preservation. Gammon also comes from the hind leg but it is cured as part of a side of bacon and cut off after wards. Gammon may be smoked separately or left unsmoked but it is not matured long enough to have a strong ham flavor and does not keep for as long as ham, which is generally cured more slowly. While some hams are meant for further cooking, some such as Parma and Bayonne hams are simply eaten in the 'raw' cured state, having been salted and then dried over several months to preserve the flesh.
Hams may also be smoked over a slow fire, and the different types of wood used, such as beech, juniper or oak, will each produce a distinctive flavor. Unsmoked hams are also known as green hams and have a milder flavor.
You can buy an uncooked whole ham to bake as a special dish, but in most stores, the ham is sold cooked and sliced, and is used for salads and sandwiches, or included in recipes where it just needs to be heated through. Gammon can be hard to find, but is available from specialist butchers especially if they sell traditional British cuts. It is sold in joints, rashers or steaks for cooking at home.
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