Boiling

In cookery, boiling is cooking food in boiling water, or other water-based liquid such as milk. A synonym is poaching, particularly when referring to eggs and fish. Boiling generates bubbles of steam that agitate the liquid, increasing heat transfer. Pure water boils at exactly 100°C if at 1 atmosphere pressure, but it boils at a much lower temperature at higher altitudes. Cooking in water that is slightly cooler than the boiling point, between 95°C and 97°C, is called simmering or seething.

Pressure cooking is an accelerated version of boiling. When under pressure, water boils at a much higher temperature and so things are cooked faster.