A powerful technology at the bottom of the ocean is why you can see this article

If you thought your internet data and international phone calls were transmitted via satellite, you would be wrong. (It’s ok, I was, too.)

Nearly all of that data actually travels on submarine cables stretching hundreds of thousands of miles along the ocean floor.

This animation shows just how many stretch from coast to coast to coast, carrying tweets, YouTube videos, phone calls, and banking transactions as they go.

Take a moment to appreciate just how pervasive undersea cables are, how they survive more than 25,000 feet below the water, and ultimately help you access this article on a distant server.

Contrary to popular belief, satellites carry less than 1% of human communications. Submarine cables carry the rest.

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The global network of submarine cables is huge -- more than 550,000 miles long.

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If you stretched all the cables in the ocean end-to-end, they would be long enough to reach the moon and back -- with slack to spare.


The first telegraph cable across the English Channel was laid in 1850, and they have increased in number and sophistication ever since. This ship installed one of the first Transatlantic Telegraph Cables.

But it was slow. The first messages in the mid-1800s took two minutes to transmit a single character.

The Telegraph Room at the White House in 1923.

The heart of every cable is a bundle of hair-thin fibre optic wires sheathed in steel, copper, and plastic. Companies may add more layers to protect the cables from ships and sea life.

The lightest cables, laid primarily in the deep ocean, are about the same size as a garden hose and simply lie along the seabed.

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Perhaps attracted by the cables' magnetic fields -- or just the opportunity to bite something -- sharks can and do chomp on them. It rarely happens but can ruin the cable.

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With as much time and money a single cable costs, and how reliant the modern world is on them, it pays to protect -- and admire -- our hidden, global internet communications system.

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