I know photons all move at the speed of light and they move in a wave like pattern. So the question is. Do we take into account the up and down motion of the wave when we measure how fast it's moving or do we just measure the forward movement ?? For example, if the wave has higher and lower ups and downs would the wave cover more "ground" than a wave with lower ups and downs in the rate of speed forward? Please be kind with any response and if anyone is confused with what i'm asking I will try to draw out what i'm asking. and a big thank you ahead of time to anyone that responds.