The heat may be added underneath the food, or above, or both. A barbecue is a typical machine for outdoor cooking using coke or other fuel for providing heat from underneath. Overhead grilling is more usual indoors, especially in professional kitchens.
In the United States, there are cook-off grills, which are competitions. The most common meats used are steak, burgers and hot dogs. Grilling food is very common for holidays or celebrations like the 4th of July (United States Independence Day). Most people use a grill more outdoors in the summer time.