What is meant by pressure cooking?

The principle behind pressure cooking is quite a simple one. Basically the pressure cooker’s lid is weighted down and sealed with a gasket which means that steam is prevented from escaping.

Liquids come to a boil under a locked lid. Steam is trapped; the pressure rises. As the pressure rises, so does the temperature. The temperature will exceed boiling point and cook the food at around 122 °C when the pressure is at its highest, reducing cooking times by about two thirds.

Other liquids, even the meted fat form meat, begin simmering away at higher temperatures than their stated boiling points. Those liquids are now superheating the food, cooking it in less time.

Among the benefits of pressure cooking including:
*Pressure cooking saves time
*Pressure cooking preserves vitamins and flavor
*Pressure cooking conserves water and energy
*Pressure cooking cleanup is easy
What is meant by pressure cooking?