The FAA established Air Route Traffic Control Centers (ARTCC). They where not all created at once but they attempt to reflect the volume of flights and major airports that exist within each region. As general aviation pilots or plane spotting enthusiast we might have some depth of understanding as to why certain border exists. However, the genral public probably does not see the immediate rational. When in-flight, it is not obvious that our commercial flight has been handed off from one center to another (unless the air traffic control audio is made available). We assume this works like a trail being routed onto the right tracks when it leaves a large train station.

What systems in our enterprise works like the ARTCC? Which need explanation to those we serve and which ones operate in the background and provide social benefit without being highlighted?