The mold that is used to cook waffles is a heavy, heat-retaining device with a top and bottom compartment. The mold is gridded in a rectangular fashion such that protrusions on the top portion are complemented by depressions in the bottom (and vice versa). Because waffle molds were historically made out of cast iron, the device has come to be known as a "Waffle Iron". Today, aluminum and steel are the principal metals used to manufacture waffle "irons".
That said, quite a few users say that this waffle maker isn't as sturdily built as previous versions of the same model, and that if you don't get the top heating plate aligned just right, it can fall off -- an injury hazard if the plate is hot. The top of the G48TD also gets very hot. Some use pliers to bend the metal clips that hold the heating plates in place, which helps them line up better -- or you can just use an oven mitt to protect your hands.