Beef is the culinary name for meat from cattle, particularly skeletal muscle. Humans have been eating beef since prehistoric times. Cow meat is a source of high-quality protein and nutrients. Butchers cut beef skeletal merely into certain parts like roasts, short ribs or steak (filet mignon, sirloin steak, rump steak, rib steak, rib eye steak, hanger steak), Other cuts need further processing (like corned beef or cecina). On the other hand, butchers and chef mix trimmings with meat from older, leaner and tougher cattle. These parts need to be grounded, minced or stuffed in sausages. The blood of cows can be used in some varieties of blood sausage. Other edible parts are offal, such as the oxtail, liver, tongue, tripe, glands (particularly the pancreas and thymus, referred to as sweetbread) and heart.