Home > Encyclopedia of Science > Heat

• Thermal energy and temperature
• Heat Transfer
• Heat units
• Specific heat

Heat is the energy that flows between two objects because of a difference in temperature. Heat always flows from a body at a higher temperature to one at a lower temperature.

Scientists use the term heat differently than do nonscientists. The average person may think of heat as the amount of energy contained in a body. The correct term for that property, however, is thermal energy.

Thermal energy and temperature

According to the kinetic theory of matter, all matter is composed of particles that are constantly in motion. Temperature is a measure of the motion of those particles. The more rapidly particles are in motion, the higher the...