The grilling process cooks foods over a high heat source, either directly, indirectly, or a combination of both. The high heat of grilling sears the surface of beef, creating tender meat with a flavorful crust. The required cooking temperature and the method of grilling depend on the cut of beef and the quality of the meat. As with any cooking method, beef that is grilled should not be overcooked in order to produce the best results. Beef can be grilled on several types of grilling units. Some grills are designed for outdoor use, while others are used indoors. There are several popular methods for grilling beef outdoors, all of which provide a flavor to the meat that is difficult to match with indoor grilling. Some beef cuts may require some preliminary preparation, such as boning, trimming, tying, or tenderizing, before they are grilled. Cooking with direct heat is accomplished by placing cuts of beef on a grate directly over the heat source. For outdoor grilling, the grate can be positioned over an open fire or wood burning grilling unit, a charcoal grill, or a gas grill.