Heat transfer is the movement of thermal energy from one object or system to another due to a temperature difference. It occurs through three primary mechanisms: conduction, convection, and radiation. Conduction transfers heat through direct contact between molecules, commonly seen when a metal spoon becomes hot in a cup of tea. Convection occurs through the movement of fluids such as liquids or gases, where warmer particles rise and cooler particles sink, creating continuous circulation. Radiation transfers heat through electromagnetic waves and does not require any physical medium, which is why the Sun can warm the Earth through space. Understanding these three fundamentals is essential in engineering, physics, environmental science, and everyday thermal systems.
