Food is cooked directly on the rack or grate of the grill. Thus, the best kinds of foods for cooking on a grill tend to be meats and poultry, although firm fish and seafood and also vegetables can be cooked on the grill.
Because a grill cooks with high-temperature dry heat, meats that are cooked on a grill should be tender cuts of meat, and marinating can be helpful to retain moisture.
The word grill can also be used as a verb to indicate cooking on a grill. Sometimes the word grill can be used interchangeably with the word barbecue. But technically, barbecuing is a form of grilling over wood or charcoal.
One of the characteristics of food cooked on a grill are the grill marks from the grate or rack. This effect can be obtained by using a specially made pan called a grill pan (compare prices). A grill pan has raised ridges that can produce grill marks, but cooking on a grill pan isn't really grilling.