A hot plate is an adjustable heating source which is ideal for heating beakers, erlenmeyer flasks, hot water baths, and other flat-bottomed containers. It is essentially an el…ectric stove top that is used in the laboratory. The temperature is adjustable (usually on a scale of 0 to 10) and there is very often a built in spinning magnetic stirrer (to be used in combination with a magnetic star bar) so that you can efficiently stir a solution while heating it. Some have computer controllers to maintain the temperature at an exact level (for instance when using a water or oil bath). A hot plate or heating mantle should always be used in place of a Bunsen burner or other open-flame source to heat a flammable liquid. See the Related Questions and Web Links to the left for more information.