Glass stove tops utilize electromagnetism to produce heat for cooking food. Each glass stove top contains an electronically-controlled metal coil, that creates a magnetic field, which in turn heats the pot or pan and the food contained therein.
The method of heat production of glass stove tops is referred to as induction heating. Appliances that utilize induction heating can be set to very specific temperatures at both high and low heat. Induction heating is also an energy-efficient method of cooking and generally cooks food slightly faster than electric and gas stoves. Furthermore, stoves that use induction heat do not warm up the rest of the kitchen and the stove top itself stays cool to the touch.
There are disadvantages to using glass stove tops and induction heating, however. Glass stove tops can scratch easily, and certain foods, such as tortillas, cannot be prepared with this method. Iron is the only metal that can effectively produce electrical heat from magnetic fields, so any pots or pans to be used for cooking must have a high concentration of iron. Other cookware made of copper, stoneware or glass cannot be used. The stove top's magnetic field may also cause pots to rattle and pots and pans with ill-fitting lids may produce loud noises.