A steer is divided into 8 main regions, which are called primal cuts. From there, the primal cuts are divided into subprimal cuts for foodservice and can then be further broken down into portion cuts, or retail cuts.
Primal Cuts of Beef
There are 8 main primal cuts of beef: chuck, rib, loin (consisting of the short loin and the sirloin), round, flank, plate, brisket, and shank. Divided by groups of muscles, the meat from each primal has its own unique flavor, texture, and level of fat and marbling due to how hard the muscles were worked.
Subprimal Cuts of Beef
Primals are cut and divided into subprimals, also known as "foodservice cuts." These large cuts are often purchased by restaurants in order to save money over buying individual steaks and to allow chefs to have full control over how their meat is cut and trimmed. Subprimals are further trimmed down into portion cuts, such as steaks, roasts, and ribs, which typically appear in grocery stores and on restaurant menus.
Best Cuts of Beef
The most tender cuts of beef come from the primals that are located farthest from the head and hooves, towards the center of the cow. These are some of the least hard-working muscles on the animal, so they lack dense connective tissue. On the other hand, the primals that make up the legs and rump of the cow are not as tender but offer a rich, beefy flavor. These strong muscles work hard during the animal's lifetime, developing rich fat marbling throughout the meat and a good deal of connective tissue.