Red light green light yellow light go ?

Sometimes for many reasons I find my self runnning a red light. I always feel like I should have stopped but then I notice, the two cars behind me also went through. What are they thinking about?

I think I screwed up and I know they did. We have the three light system for one reason, transition. What if there was no yellow and we all had to slam on brakes when the light turns red? There is a total lack of respect for yellow. Yellow means warning and most are unwilling to heed the warning. These rebels know about the delay, from when their light turns red and the opposite light turns green. They are exploiting the delay for their own selfish gain at everyones risk. How far must one get under the light  to have made it and not ran it? Pass the white stripe, half way through or as long you can`t see it change? There is one acceptable situation for running a red light, turning left and having to yield to traffic. In this situation you must move out in the intersection and turn when your sure the other cars are stopping usually after both lights turn are red. Remember the life you save may be mine.