Convection is the transfer of heat by the movement of a fluid. In convection, the fluid is heated at the bottom and rises, while the cooler fluid sinks. This creates a convection current, which is the movement of the fluid in a circular pattern. The convection current continues until the fluid is evenly heated.

Convection is an important process in the Earth's atmosphere and oceans. It is responsible for the formation of clouds and storms, and it also helps to regulate the Earth's temperature. Convection is also used in many industrial applications, such as heating and cooling systems.