Curing is actually a general term referring to any process that helps preserve meat. It can mean salting, brining, aging, drying or canning. The goal of all of these processes is to slow spoilage and prevent the growth of microorganisms.
None of these curing processes is necessarily better or worse, and choosing one over the other often depends on the desired end result. Basic salting and brining is best for short-term preservation, while aging, drying, and canning all result in a product that can be stored for much longer. Products like beef jerky and salt cod can last almost indefinitely!
Salt is a key ingredient to almost all curing processes. Whether it's applied in a dry-rub or as part of a brining solution, the salt works to draw moisture out of the meat. The less moisture in the meat, the longer it can be saved before being eaten.
Additionally, nitrites can be added to the curing mixture as further insurance against bacterial growth. Smoking the meat also helps prevent spoilage and keep the fats in the meat from going rancid.
All cured meat products have undergone some sort of curing process. However, this shouldn't be taken as a guarantee that the product won't eventually spoil or that it can be eaten raw! Be sure to go by the expiration date on the product labeling (or what your butcher tells you) and cook meat thoroughly unless otherwise stated.
Related: The Skinny on (Uncured) Beef Bacon