Technology
Elisha Otis sold safety, not elevators
His 1854 demo had an assistant cut the cable while he stood on the platform. The spring-loaded brake caught it instantly — and made tall buildings possible.
More in Technology
The internet travels as pulses of light
Fibre optic cables carry data as laser light bouncing inside glass thinner than a hair, moving at roughly two-thirds the speed of light in vacuum.
Almost all international data crosses the seabed
Satellites carry a tiny share — around 99% of intercontinental internet traffic runs through submarine cables, some no thicker than a garden hose.
GPS would fail without Einstein
Satellite clocks tick faster in weaker gravity and slower from speed. Without relativity corrections of about 38 microseconds a day, positions would drift kilometres off.
Moore's law was an observation, not a law
In 1965 Gordon Moore noticed transistor counts doubling roughly every year, later revised to two. That guess became the industry's roadmap for half a century.
Your battery works by shuttling lithium ions
Charging pushes ions into the graphite anode, using them pushes them back. Each cycle degrades the structure slightly — which is why batteries age.
Touchscreens sense your body's electricity
Capacitive screens hold a tiny electrical field; your conductive finger distorts it, and the phone calculates where. That is why gloves usually do not work.