It's 2 am, most people are asleep in their beds, and you have a to catch a plane at 5. You decided to stay awake (because that's probably how late you would've stayed up on a weekend anyway), but no you're exhausted, so you have to hustle to put some coffee in a thermos and rush out the door, plugging your destination into Waze (because…dog car).

It's a beautiful night with no one on the road, which means…the construction night crews are out doing their thing.

Ugh.

To get to the airport on time, you have to pass the highway exit you usually take. At this point, Waze might be a little confused, but it recalculates and tells you where to go so that you can still make it to the airport.

Handy, right?

On the internet, a router works just like Waze, except it helps packets get between two computers instead of helping lost Shmoopers make their flight. Information on the internet reaches its destination so quickly because legions of routers monitor the movement of packets and change routes if they need to make sure that traffic flows like it should—even if a network goes down.

With the help of some complex algorithms, routers determine the best path for packets to travel and direct them along those paths. If any problems pop up on the network, like if one pathway gets clogged with too much data or a sinkhole swallows up another, the routers recalculate a new route for your packets to travel so they can get to the airport your friend’s computer.

Now if only there was a way to reroute traffic quickly in the real world…

(Source 1, Source 2)