The Hirsch's Meats website features a diagram of the prime cuts of beef. Images of smaller cuts are included, along with information about how each cut is used. About.com has a diagram that shows cuts of pork and information about each cut's use.
Prime beef cuts include the chuck, rib and various sirloins. A prime cut may be divided into smaller cuts for retail. For example, the chuck includes bone-in chuck steaks and boneless clod steaks.
The same cutting process takes place for pork. The most tender cuts are from the loin and the rib, which are in the pig's center. Tougher cuts, such as the shoulder, must be cooked correctly in order to become tender.