electromagnetic radiation

• ejects photons/electromagnetic waves (e.g. radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma radiation (γ))

particle radiation

• ejects particles of non-zero rest energy
  • alpha radiation - ejects helium nucleus
  • beta radiation - ejects electrons
  • neutron radiation - ejects neutrons

gravitational radiation

• radiation that takes the form of gravitational waves, or ripples in the curvature of spacetime

acoustic radiation

• as ultrasound, sound, and seismic waves (dependent on a physical transmission medium)