Lots of confusion, time for some BACONOLOGY:
In the United States the USDA defines bacon as "the cured belly of a swine carcass"; other cuts and characteristics must be separately qualified such as "smoked pork loin bacon". Four 14-gram (0.5 oz) slices of bacon together contain 7.45 grams (0.26 oz) of fat, of which about half is monounsaturated, a third is saturated and a sixth is polyunsaturated, and 7.72 grams (0.27 oz) of protein. Four pieces of bacon can also contain up to 800 mg of sodium, which is roughly equivalent to 1.92 grams of salt. The fat and protein content varies depending on the cut and cooking method. As far as the "drippings" are concerned, One teaspoon (4 g or 0.14 oz) of bacon grease has 38 calories (160 kJ). It is composed almost completely of fat, with very little additional nutritional value. Bacon fat is roughly 40% saturated.
There are various types of bacon depending upon the cut of meat from which rashers are derived:
Side bacon, comes from pork belly. It is very fatty with long layers of fat running parallel to the rind. This is the most common form of bacon in the United States.
Pancetta is Italian streaky bacon, smoked or aqua (unsmoked), with a strong flavor. It is generally rolled up into cylinders after curing.
Middle bacon (Australia/New Zeland), from the side of the animal, is intermediate in cost, fat content, and flavor between streaky bacon and back bacon.
Back bacon (rashers or, in the United States, Canadian bacon) comes from the loin in the middle of the back of the pig. It is a very lean, meaty cut of bacon, with less fat compared to other cuts. It has a ham-like texture. Most bacon consumed in the United Kingdom is back bacon.
Cottage bacon is thinly sliced lean pork meat from a shoulder cut that is typically oval shaped and meaty. It is cured and then sliced into round pieces for baking or frying.
Jowl bacon is cured and smoked cheeks of pork.
Slab bacon typically has a medium to very high fraction of fat. It is made from the belly and side cuts, and from fatback.
Collar bacon is taken from the back of a pig near the head.
Hock, from the hog ankle joint between the ham and the foot.
Gammon, from the hind leg, traditionally "Wiltshire cured".
Picnic bacon is from the picnic cut, which includes the shoulder beneath the blade. It is fairly lean, but tougher than most pork cuts.