What is the definition of radiation?

Radiation is defined as the transfer of energy through electromagnetic waves. This process does not require a medium, allowing thermal energy to travel through a vacuum, such as space. Unlike conduction, which relies on direct contact between materials, and convection, which involves the movement of fluid currents, radiation can occur in empty spaces. This is the principle behind how the Sun’s energy reaches the Earth. The electromagnetic waves involved can include visible light, infrared, and other forms of radiation, all contributing to energy transfer without any need for physical contact or a medium. Understanding this definition is crucial for grasping concepts in thermodynamics and energy transfer mechanisms.