I am extremely confused with why time dilation is different from what I've read about traveling at speeds near that of light. I think that I am mixing up two concepts. What I understand is that due to time dilation, both observers would view the other's clock as running slow as long as both are traveling at constant velocities. However, I also thought that if one was traveling near the speed of light and the other was at a lower velocity or "stationary" the the clocks would be different by a factor depending on how close to the speed of light so that the "moving" observer would have aged less than the stationary observer. Basically, how does one age so that their clock was slower and the other was faster, but at the same time both would observe the other's clock to be slower?