Thread: questions about light

I think I am really having trouble understanding some basic things about light. My main question is:

How are Electromagnetic waves created? I've read that electric fields create magnetic fields which in turn create electric fields, but wouldn't this mean that both electric currents and magnets should emit EM waves? Maybe these EM waves are not in the visable light spectrum, but this idea doesn't seem quite right to me. I thought that light was somehow created by friction. I think I've also read that photons are responsible for the creation of EM fields. I'm so confused.

Other questions are:

Photons are supposed to be massless particles, which to me doesn't make too much sense since something should have to have mass to be mass... unless the mass of photons fluctuates as they change speed?

Is light composed of EM waves or particles driven by EM waves (photons?)

More questions to come I'm sure.