Is there really no mass in photons?

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Photons are massless particles that carry energy, which can be confusing in light of Einstein's equation E=mc², suggesting a relationship between mass and energy. While photons possess energy and momentum, they do not have rest mass, meaning they do not have mass when at rest, as they always travel at the speed of light. The energy of photons is related to their frequency, and this energy contributes to their effects, such as in the photoelectric effect. The concept of mass in physics differentiates between rest mass and relativistic mass, with photons only exhibiting relativistic effects. Understanding this distinction clarifies how photons can exist without mass while still embodying energy.
rlinsurf
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Please be gentle to a newbie question, and to my limited understanding of the subject.

E=Mc2 as I understand it means that there is an equivalency between Mass and Energy, that essentially, mass is energy, and so the more energy of one kind or another there is, the more mass there is.

In that case, since we know there are several kinds of energy in photons, how can they have no mass?

Thanks.
 
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Thanks. I think I got it.

All My
Jeffrey
 
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