Author's Note: How WiFi Works -- Bernadette Johnson
I worked on an update to the content of this article, and I think it's amazing that in a few scant years we've gone from mostly wired to mostly wireless data transfer, via WiFi in our homes and public places, as well as cell phones. Of course, a lot of the infrastructure still uses wires, but the fact that we can communicate via both radio waves and electricity traveling through wires is pretty incredible. A big thanks to the inventors of the telegraph and every communication innovation that came after.
I remember the days when most mere mortals didn't have modems and couldn't get on the net, even if they had computers. Perhaps I'm projecting my experiences onto everyone else, but when I was a kid, our computer was this tool we used in isolation, save for the times friends would come over to play video games. My computer programmer aunt was the only person I knew who had a modem. It was the type where you put your phone directly onto a cradle and some crazy analog communication went on.
When modems became widespread, they were still these clunky external things that we hooked up to our computers to noisily and slowly dial up to a larval Internet. They tied up the phone line, so you couldn't keep them connected indefinitely, and if you didn't want to run up an astronomical phone bill you had to make sure you were using a phone number for a local access point. Modems went internal and got a bit faster, but now dial-up is going the way of the dodo bird due to the ubiquity of affordable broadband services in the home like DSL and cable.
With an astounding jump in bandwidth, and the ability of our computers to connect wirelessly, many of us are online all the time, and free to compute all over the house or even away from home. I've surfed the net, streamed shows and downloaded books while on vacation via hotel, airport and other hotspots. And I fall asleep nightly streaming Netflix on my WiFi-only tablet at home. Which is great, aside from the fact that I really should be resting. But insomnia and information overload are topics for another time.
(Source: How stuff works?)