To steam means to cook food completely surrounded by water vapor at a temperature of 212°F (100°C) or higher. There are two ways to steam foods:
Stovetop steaming: Done in a compartmented pan on a stove burner. While stovetop steaming is common in Asian restaurants, in Western cuisines it is more typically utilized in home cooking.
Pressure steaming: A specialized, high-temperature form of steaming used in professional kitchens. Pressure steaming is the ideal way to efficiently and quickly soften vegetable fiber while preventing acid concentration.