Some 110 million U.S. households use a range–or cooktop and oven–for cooking. About two-thirds of those are powered by electricity, while one-third use natural gas or other fuels. But of the electric-powered majority, only a tiny percentage use what’s called induction. Though induction stoves might look like other electric stovetops, there’s some fascinating science that sets them apart from both gas and traditional electric stoves. 

In a gas stove, natural gas or another fuel like propane is ignited to create a flame that can quickly be turned to the desired level. Electric ranges, on the other hand, come in a variety of styles, but all rely on a heating coil. Once the power is turned on, alternating current sends a rush of electrons around the coil. But the electrons aren’t on a slip-n-slide: The coil itself is designed to resist the electron flow, priming the particles to release their energy as heat. This process of building up the heat means it takes longer for an electric burner to reach the desired temperature than an instantly adjustable gas burner.

At a glance, induction cooktops may resemble traditional electric ones—both can have smooth, glass tops with coils powered by electricity. But induction cooktops use electricity in a slightly different way to heat up your pans.

In contrast to traditional electric stoves, the coil inside an induction cooktop does not itself generate heat. In fact, the coil is designed with metals that conduct electricity rather than resist it. As the alternating current flows from the power socket into the metal coil, it forms a magnetic field. This magnetic field can interact with ferromagnetic materials, like the iron in a cast iron skillet or the alloys in a stainless steel pan, to create small currents in those metals. The pan itself then acts like a traditional heating coil, resisting those currents and causing the electrons to release their energy as heat.

This method of heating is possible because ferromagnetic materials have magnetic domains, or groups of atoms that are aligned in such a way that they can be collectively influenced by a magnetic field. This is why induction stovetops only work with pots and pans made of magnetic materials—and they won’t directly heat up other things, like aluminum pans or the skin on your hand.

Like a gas stove, an induction stove can be adjusted up and down immediately, heating food quickly and efficiently. According to Energy Star, roughly about 85% of the electricity consumed by induction stovetops actually goes toward heating your food. By contrast, traditional electric stoves have an efficiency of 75-80%, and gas stoves are 32% efficient.