Mike Pusateri shows how he made bacon from pork belly.
The first step is curing the pork belly with a dry cure of salt, sugar, and pink salt (sodium nitrite). The main purpose of the cure is to prevent any bacterial growth on the meat and draw out some water.
Let's remember that refrigeration is a relatively new invention. In the past, a big life problem was finding ways to preserve meat for use long after it was killed. Curing by salting, smoking, and drying are methods to prevent meat from spoiling. Making bacon was a way to save the pork belly for later use. Pork belly was also the main ingredient of salt pork, a mainstay of the military diet for centuries.