How does Wi-Fi work?

Wi-Fi uses antennas around which Wi-Fi ‘hotspots’ are created. The hotspots are outlets equipped to receive the radiowaves that power wireless networking. Until recently, Wi-Fi has been confined to more than 10,000 hot-spots in cafes, bars and airport lounges. But various projects are under way to set up city-wide zones, where a series of antennas are installed in the streets, on lampposts or street signs. The hotspots around them together create a much wider area of coverage.
The source internet connection is provided by a PC or server to which the antennas are connected either wirelessly or via a cable.
Some mobile phones and personal digital assistants (PDAs) now have Wi-Fi chips installed. With mobile phones, this means conventional networks can be bypassed and inexpensive long-distance calls made over the web using Voice over Internet Protocol (VoIP).
Many laptops and handheld computers now come with built-in Wi-Fi connectivity. It is also possible to add Wi-Fi to your computer with a special card that plugs into a port on your laptop.