Originally Posted By: Bill S.
Are you talking about invariant mass, or some more esoteric form of mass?

I am talking about the mass in the normal sense, ie, the mass represents the amount of matter in it. In my view, the photons are made up of fundamental particles of matter, each photon containing the required number of particles. The energy that a photon possesses is kinetic energy due to its motion at the speed 'c'.