When cooking in a pressure cooker, we add the raw food (dry rice, dal, vegetable, or meat) and water. Then we seal the cooker container with the lid and heat it on the stove. Slowly the temperature of the water increases. As the container is closed along with the steam stop valve, the inner volume cannot expand. For this reason, the pressure inside the cooker grows, increasing the boiling point of water. Thus, water does not convert into steam fast, but the temperature continuously increases, making the cooking faster. This is why a pressure cooker reduces cooking time