Heat is one of the most important forms of energy. When we think of heat, we usually think of how heat makes us feel. On a hot day, for example, it may make us feel uncomfortable. But heat is far more important in our lives than simply how it may make us feel.
We must have a carefully controlled amount of heat to live. Our bodies use the food we eat to produce the heat that keeps our temperature at about 98.6 °F (37 °C). If our body temperature rises too far above normal
