But unlike a highway or a forest, it exists in places we usually do not see. These words, for example, were originally stored on the tiny magnets of a hard drive attached to one of Quartz's servers in Washington, DC — a tiny leaf on the edge of the internet.

When you clicked on this story that server heard you, retrieved our words and images from the magnets, and then shipped them to you through a branching maze of wires and computers.

The very last computer in our data center took those words and did something miraculous with them: It transformed them into light.

Those pulses of light crossed under the streets to another computer, on another network, which decided where to send them next. Then another computer did the same thing. Then another.

Depending on where you are sitting now, our words could have touched (and changed) dozens of other computers on their way to you.

Those computers are made of different materials, were installed by the hands of different owners, and are bound by the laws of different countries. If you're lucky, none of them changed these words or snooped on your reading choice before they reached you.

What allows all this to happen is the most complex piece of physical infrastructure ever created. Though few parts of it actually touch, the internet is, nevertheless, as interconnected as a forest.

Every word and image on it is constantly being converted back and forth between magnetic recordings on spinning silver disks, electrical signals on hair's-breadth wires, flashes in tiny glass tunnels, and electromagnetic waves oscillating through the air.

Its roots are deep under the oceans and its branches extend out to myriad satellites, orbiting in space.

As it has grown, the internet's many limbs have crossed borders, transformed our culture, drawn bold lines between freedom and autocracy, changed the way we love and work, and allowed Quartz to deliver news to you on the subway. The internet is all around us, yet difficult to find.

That's why we need a map.