Heat transfer occurs through three primary mechanisms: conduction, convection, and radiation.
Conduction is the transfer of heat in solids, moving from hotter to cooler regions.
Convection takes place in fluids (liquids or gases) via the movement of heated particles that carry energy.
Radiation transmits heat through electromagnetic waves, independent of a medium.
Transmission, while a general term for movement between points, is not a distinct mode of heat transfer.
In thermodynamics, the accurate terminology for heat transfer modes is conduction, convection, and radiation.