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The internet isn't in the sky — it's on the seafloor
💡 The global internet runs mostly through thin fiber-optic cables on the ocean floor, not through satellites overhead.
When you load a website hosted on another continent, your data almost certainly did not travel by satellite. Instead, it raced through a submarine cable lying on the ocean floor. Roughly 99% of all intercontinental internet traffic — web pages, video calls, bank transfers — moves through a global web of these cables, not through space. Satellites handle only a tiny fraction, because light through glass fiber is far faster and higher-capacity than a signal bounced off an orbiting relay.
E ach cable is surprisingly thin — often about the diameter of a garden hose — yet it can carry hundreds of terabits per second. At its heart are hair-thin strands of optical fiber that guide pulses of laser light. Wrapped around them are layers of steel wire, a copper conductor, and waterproof insulation for protection and power delivery.
Because light fades over distance, repeaters spaced along the cable amplify the signal — powered by that copper conductor from shore. When a cable fails, it's rarely a dramatic event: most faults come from fishing gear and ship anchors in shallow water, and specialized repair ships haul the cable up to splice it back together. Sharks biting cables makes headlines, but it's a minor cause.