A pork loin is a cut of meat from a pig that is created from the tissue along the dorsal side of the rib cage. Pork loin is a popular meat due to its flavour and juiciness.
One reason why a person might want to buy a whole pork loin instead of a boneless loin is that the bone can give the meat added flavour. This is often a reason to cook the meat with the bone, even though this can make certain recipes more complicated.