A drop of water can skate across a hot pan

Above a critical temperature a drop does not wet the surface. It floats on its own vapour and lasts much longer than it would on a merely hot pan.

Johann Gottlob Leidenfrost described it in 1756. Below the Leidenfrost point a drop spreads, boils, and is gone. Above it, the bottom of the drop vaporises so fast that a gas layer holds the liquid off the metal. Heat has to cross that layer, so the drop is insulated and can wander for a minute, hissing quietly.

The temperature of the point depends on the liquid and the surface. For water on a clean pan it is well above boiling, often around 150 to 200 °C, and it moves if the surface is rough or coated. The vapour layer is thin and fragile. The moment it collapses, the drop wets the surface and boils at once.