What is the process of heat transfer by the movement of a gas or liquid called?

The process of heat transfer by the movement of a gas or liquid is known as convection. This occurs when warmer areas of a fluid rise and cooler areas sink, creating a cycle that transfers heat throughout the substance. Convection is essential in many natural and engineered systems, such as atmospheric weather patterns, ocean currents, and heating systems in buildings.

In contrast, conduction refers to heat transfer through direct contact between materials, where heat flows from a hot object to a cooler one without the movement of the material itself. Radiation involves the transfer of heat through electromagnetic waves, allowing energy to travel through a vacuum, such as heat from the sun. Absorption typically describes a material's ability to take in energy or light rather than the movement of heat through fluids. Understanding convection is crucial in fire and life safety, as it influences how smoke and heat behave in a fire environment.