The internet consists of tiny bits of data that move around the world, travelling along the thinnest of wires which have been laid across the ocean floor – from London to New York to Hong Kong to Sydney in the time it takes you to read these words.

An almost unbelievable 750,000 miles of cable already connect the continents to support our demand for communication and entertainment, and historically, companies have worked together to collaborate on undersea cable projects – a bit like a massive shared motorway.

But now Google has begun a solo project to connect the United States to Chile where it has its largest data centre in Latin America. And it’s going to do it through cables at the bottom of the sea.

The cables start out as a cluster of strands of tiny threads of glass fibres. Then the fibres are wrapped in a copper casing that carries electricity across the line to keep the data moving. Plastic, steel and tar are added later to help withstand unpredictable ocean environments. In the end, the cables are the size of a thick garden hose. Lasers send data down the threads at nearly the speed of light and after reaching land and connecting with an existing network, the data needed to read an email or open a web page makes its way onto a person’s device.

But you can’t just lay the cables once they’ve been made. It takes about a year of planning to chart a cable route as they must be able to withstand rock slides, heavy currents, undersea earthquakes and interference from fishing trawlers – and last up to 25 years.

And though most of us experience the internet through wi-fi and phone data plans, we don’t always realise that those systems eventually link up with physical cables that carry the information across oceans.

Perhaps most surprisingly, and despite incredibly sophisticated new wireless and satellite technologies, cables remain the least expensive, fastest and most efficient way to send information across oceans.