The Question
Before I start discussing this topic, I want to talk a bit about the speed of light. That pesky limit basically means that there is an inherent lag in passing information between any two points in space. In your daily life, you can mostly ignore it. The human brain is far too slow to perceive it, and even if you are working with computers, you can usually ignore the speed of light for anything less than about 500 miles.
But the speed of light is merely the hard upper limit of our ability to send information from one location to another. In practice, the lag time between any two computers connected to a network is much higher. In fact, if you are a gamer, you are very well acquainted with that fact.