Radiation occurs when energy is transferred by electromagnetic waves

Thermal or Heat energy

Explanation:

There are three ways through which heat transfer, it include conduction, convection and radiation, so radiation is the type of heat transfer.

Electromagnetic waves are those waves which travel with the speed of light. These are generated as the result of vibration between magnetic and electric field and these fields transfer heat or thermal energy through a medium or across vacuum by the process of electromagnetic radiation.

Electromagnetic waves ARE radiation.

A wave always carries energy.