Patented by Albert Marsh in 1906, nichrome was the first practical resistance-heating alloy and enabled the electric toaster.
On heating it grows an adherent chromium-oxide skin that lets elements glow at up to about 1,200 °C in air without scaling away.
Its resistivity of roughly 1.0-1.1 microohm-meters changes little with temperature, giving stable output in hair dryers, kilns, and hot-wire foam cutters.