The exception is hamburgers and steaks which are at high heat and indirect. Some people like to sear steaks and hamburgers at high heat and direct, and then move the heat to indirect. Chicken or ribs are a snap to barbecue at low heat and indirect. Simply baste with your favorite sauce in the last 15 minutes of cooking. As with any barbecuing, always use a tongs rather than a fork to turn the meat to avoid the loss of juice.
Fish is a real treat on the grill.
If you have not tried fish on the gill, you should. This is just to keep the fish from sticking to the grill. You might wish to review the ABC's of Fish. I do not marinate fish before grilling it as I like the taste of fish, and I serve it with lemon for seasoning. Marinating is what separates the serious barbecue fan from the casual one.