Wi-Fi offers one of several wireless network technologies that allows computers and other devices to connect to each other inside a local area network and to the internet, without wires and cables. With Bluetooth, Wi-Fi is the de facto standard for wireless networking.
Wi-Fi governs wireless LANs through protocol 802.11.
Contrary to popular belief, Wi-Fi doesn't stand for wireless fidelity. In fact, Wi-Fi doesn't stand for anything at all. The term is merely a trade name for WLAN technology.
Wi-Fi's Worth and Limitations
The greatest advantage of Wi-Fi is the portability it offers to people using laptop computers and handheld devices like smart phones and PDAs—they can switch from one network to another without the hassle of worrying about wires, and new devices may join the network without explicit provisioning by a network admin provided the device offers the proper passcode credentials.
Wi-Fi has one serious limitation. Because it is a LAN technology, Wi-Fi offers a limited connection range, usually of 60 feet or less depending on obstructions between a device and a router. A W-iFi antenna sends waves everywhere around it in a sphere. The Wi-Fi signals lose intensity as they move further away from the antenna, which is why the quality of the connection decreases as the computer or device is placed further away from the source. Wi-Fi connection management applications on computers and other devices often indicate levels for grading the strength of the connection: excellent, good, fair, or poor.
Wi-Fi Protocol 802.11
Wi-Fi is a protocol specifying a series of rules governing how data transmission carries on a network. The IEEE (a governing authority) specified protocol 802.11 for the family of standards that includes Wi-Fi. This base standard number is normally followed by a letter denoting a revision. For example, modern home routers transmit using 802.11ac or 802.11n protocols.
What You Need for Wi-Fi
Because Wi-Fi signals attach to a router, you're free to plug any router into your home network. Most modern modems include a built-in router, so odds are good that you're already using it. For older environments offering hard-wired connections only, plugging a router into the connection then running the router's setup wizard usually works just fine.
A device must include the requisite radios to make use of Wi-Fi connections. Every modern laptop and smartphone supports Wi-Fi, but some types of desktop machines may not—but even these devices are extensible through USB receivers.