Heat exchange mechanisms.

Radiation is the absorption of electromagnetic waves without direct contact, as when a lizard basks in the sun.

Evaporation removes heat from a surface when a liquid turns to gas, as when saliva evaporates a lizard's moist surfaces.

Convection transfers heat by the movement of fluid past a surface, as when a breeze blows across a lizard's dry skin.

Conduction transfers heat by direct contact, as when a lizard sits on a hot rock.