Space and Communication
How Wi-Fi Transmits Data
Wi-Fi is ordinary radio with clever rules for sharing. Here is how bits become waves, how devices take turns, and why walls and neighbors slow you down.
Category
Space and Communication
Radio waves, light in glass, cables on the seafloor and satellites overhead: how information and time travel across long distances.
Articles in this category
5 articles · 30 quiz questions (10 easy, 10 medium, 10 hard).
Space and Communication
Why GPS Depends on Extremely Precise Clocks
GPS is really a timing system. A billionth of a second equals about 30 centimeters of error, which is why satellites carry atomic clocks and relativity must be corrected.
Space and Communication
How Fiber Optics Carry Information as Light
A strand of glass thinner than a hair can carry a flood of data. The secret is total internal reflection, extraordinarily pure glass, and light at just the right color.
Space and Communication
How Undersea Cables Keep the Internet Connected
Most intercontinental data crosses oceans through cables barely thicker than a garden hose. Here is how they are built, powered, laid, and repaired.
Space and Communication
How Satellites Enable Long-Distance Communication
A communications satellite is a radio relay in the sky. Its orbit decides how much of Earth it sees, how long signals take, and what kind of service it can offer.
Other categories
Computers and Devices
From the keyboard layout you type on to the sensors that recognize your fingerprint, everyday devices are full of design decisions with a story behind them.
Internet and Connectivity
Airplane mode, Bluetooth, the cloud and encryption: what really happens when your devices talk to each other and to the network.
Everyday Inventions
Batteries, LEDs, solar panels, microwaves and induction cooktops: the physics behind gadgets we use without a second thought.