How much liquid should I add when pressure cooking?

When cooking most foods under pressure, you should add at least 1 cup (8 ounces) of liquid to the Removable Cooking Pot, or refer to the amounts specified in the Cooking Charts. You must use sufficient liquid because the Pressure Cooker constantly builds steam during the entire cooking process; if you run out of liquid and continue cooking, the food will burn. (Page 11)