Angus beef develops with better marbling than most cattle. Marbling is the amount of intramuscular fat. Most people agree that marbling improves flavor, tenderness, and keeps meat moist while cooking (especially at high temperatures). Beef is graded based on marbling with the highest degree of marbling reserved for the Prime grade (Prime represents less than 3 percent of all beef produced). Angus frequently grades better on the USDA scale, but that doesn't mean that Angus is a grade of quality or that anything you buy labeled Angus is going to be better than any other cut.