In ancient times, stone or brick ovens that used wood for fuel were the main options for baking bread. In Colonial America, people relied on beehive-shaped brick ovens to cook their food. In the 1700s, cast iron stoves were introduced; the version invented by Count Rumford at the tail end of the century was particularly popular. His model featured a single fire source but allowed for (limited) temperature regulation; unfortunately, it was too large for smaller home kitchens. The first commercially produced gas stove was designed by James Sharp and debuted in the second half of the 19th century. Electric stoves came into use soon after, in the late 1800s. Electric or gas stoves reigned until the mid-1900s, when the first microwave oven was released by Amana, a division of Raytheon. Today most American kitchens have both a stove and a microwave for cooking food.