These words all refer to methods of cooking by direct heat or flame, especially on to of a stove. Boil implies rapid cooking in more or less large quantities of water heated to the point (212 at sea level) where bubbles escape at the surface: to boil potatoes; to boil an egg.

Simmer means to cook slowly in a hot liquid just below the boiling point, and usually for a long time.

To steam food is to cook it by direct exposure to steam or by using heat generated by steam , as in a double boiler. Direct steaming is usually accomplished by placing a metal rack above the level of shallow boiling water in a pot so that the food does not touch the water: to steam fish; to steam vegetables. Poach implies a method of cooking a few foods, such as eggs without their shells, or pieces of chicken or fish, by dropping them into hot water, milk or stock and simmering until done.

Stew is a close synonym of simmer in that both mean to cook slowly in liquid over low heat; to stew prunes. However, to most people, stew strongly suggests the familiar dish that is cooked in this way -- meat combined with vegetables in a gravy or sauce. Stewing always involves simmering, but one may simmer (not stew) soups, vegetables, sauces, etc.

When cooks speak of stewing meat, they usually mean to braise it. Braise implies the browning of meat (and often of accompanying vegetables) in a small amount of fat prior to adding a stock or other liquid and simmering in a covered pan.

Fry and sauté are closely related in that the food is cooked in hot fat. Sautéing , is done very quickly with a minimum amount of fat and may or may not imply browning. Meat is usually sautéed before it is braised . Frying suggests cooking in greater amounts of fat than that used in sautéing , and may be done in a pan containing up to one or two inches of fat or in a pot designed for deep frying , in which large amounts of fat are used. Dry-frying is the complete cooking of meat (chops, steak, etc.) by frying slowly in little or no fat. Foods, especially potatoes, cooked in deep fat until crisp are often called "French-fried ."

One pot-roasts a large piece of meat by placing it in a little fat in a large saucepan on top of the stove, so that it cooks slowly, perhaps surrounded by roasting vegetables.