Convection is the process of heat transfer that occurs due to the movement of fluids (liquids or gases). It's driven by differences in density:

* Warmer fluids are less dense and tend to rise.

* Cooler fluids are denser and tend to sink.

This continuous cycle of rising and sinking fluids creates vertical circular movements that transfer heat energy.

Examples of convection include:

* Boiling water: Hot water at the bottom rises while cooler water at the top sinks, creating convection currents.

* Weather patterns: Warm air rises, cools, and then sinks, creating wind and weather patterns.

* The Earth's mantle: Convection currents in the mantle drive plate tectonics.