Broiling is a cooking method in which food is cooked directly under high heat. Scallops or steak can be cooked under the broiler, giving them a nice caramelized crust and a juicy interior. (A broiler is also called a salamander in a professional kitchen, and is often a small, separate heat source where dishes—especially those made with cream—are given a final blast of heat before serving.
Grilling is often used as a synonym for broiling, though when we use the verb "to grill" in America, we technically mean that the food is cooked over a direct heat source, rather than under. Barbecuing, on the other hand, generally refers to cooking food over indirect heat.
To confuse matters, our British and Australian friends refer to what we call broiling as grilling; hence the term "grilled cheese," which in the U.K., is generally made open-faced and heated under a broiler, not fried in a pan in the American fashion.
Recipe: Broiled Salmon With Miso (Cookthink)
Recipe: Broiled Chicken With An Indian Spice Rub (Cookthink)