This method is concerned with sealing and browning the meat on the top of a fire or stove. The source of heat comes from glowing embers, burning vine prunings or brushwood, fruitwoods and other woods (avoiding those that are resinous) or charcoal, and the only equipment needed is the grilling rack, on which you place whatever is to be cooked.
There are also, of course, effective modern grills which work by gas, electricity, infra-red rays, or which are simply a solid disc of iron, ridged on the top and slightly at an angle, with a handle on one side, which is put straight over the source of the heat (but nobody has yet managed to reproduce the wonderful effect of wood-smoke on food).