Wi-Fi: Surfing on Radio Waves

Without Wi-Fi, your smart devices would be a little dumber. Explore the surprisingly simple principles behind this technology with Groupon’s introduction.

With its territory increasingly overtaken by the Internet, radio may seem downright old-timey. But, in fact, our experience of the Internet would be quite different without it. Wi-Fi uses two-way radio communication to transmit data, just like walkie-talkies, TVs, radios, and theatergoers trying to circumvent cell-phone bans. The process is relatively simple: a built-in wireless adapter in your computer, smartphone, or other device converts data from binary code—the language of computers that uses strings of 0s and 1s—into a radio-wave signal, which it sends into the air using an antenna. A wireless router receives the signal, converts it back into binary code, and sends it to the Internet via a wired connection with your modem. (And, of course, the process also works in reverse.) Most routers can send and receive signals within a 100-foot radius, but there are more powerful models on the market.

There are a few differences between the two-way radio communication used by radio stations and that used to power Wi-Fi. Wireless adapters and routers transmit at much higher frequencies, which allow the signal to carry more data. Radio waves sent by wireless devices can also “frequency hop” to reduce interference and allow multiple devices to use the same Wi-Fi connection.

If the Wi stands for wireless, where does the Fi come from? According to the founders of the Wi-Fi Alliance, from thin air. A branding agency coined the term to stand in for what would otherwise have been a rather cumbersome bit of technical jargon; Wi-Fi was simply a catchy and logo-friendly invention. Later, some members of The Alliance suggested the back-formation “wireless fidelity,” although it didn’t quite catch on.