In a world of drive-through banking and satellite TV, flat rate long distance shouldn't seem like a major technological triumph. For the entirety of telephone history, however, callers have been charged variable rates depending on when and where they were calling. You're not charged more to drive at peak hours on the freeway. Nor are you charged more for that burger just because it's lunch time and more people are hungry. So what gives?
The truth is, phone networks, until recently, were horribly inefficient. Voices traveling through copper wire have their advantages--copper is actually a superior medium for conduction. However it takes a lot of acreage and labor to implement a copper network. Fiber optics are much more efficient all around.
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