If you have a computer network in your home or office, there are several different ways to connect the computers together.

Wi-Fi is the wireless way to handle networking. It is also known as 802.11 networking The big advantage of Wi-Fi is its simplicity. You can connect computers anywhere in your home or office without the need for wires. The computers connect to the network using radio signals, and computers can be up to 100 feet or so apart.

In this article, we will discuss two different aspects of Wi-Fi. First we will discuss the basic technology that makes Wi-Fi networking possible. Then we will discuss the hardware you need to create a Wi-Fi network, and help you understand how to set up and access a Wi-Fi hotspot in your home.

Walkie-Talkie Network

If you want to understand wireless networking at its simplest level, think about a pair of $5 walkie-talkies. These are small radios that can transmit and receive radio signals. When you talk into a walkie-talkie, your voice is picked up by a microphone, encoded onto a radio frequency and transmitted with the antenna. Another walkie-talkie can receive the transmission with its antenna, decode your voice from the radio signal and drive a speaker.

Simple walkie-talkies like this transmit at a signal strength of about 0.25 watts, and they can transmit about 500 to 1,000 feet.

Let's imagine that you want to connect two computers together in a network using walkie-talkie technology:

You would equip each computer with a walkie-talkie.
You would give each computer a way to set whether it wants to transmit or receive.
You would give the computer a way to turn its binary 1s and 0s into two different beeps that the walkie-talkie could transmit and receive and convert back and forth between beeps and 1s/0s.

This would actually work. The only problem would be that the data rate would be very slow. A $5 walkie-talkie is designed to handle the human voice (and it's a pretty scratchy rendition at that), so you would not be able to send very much data this way. Maybe 1,000 bits per second.

Wi-Fi's Radio Technology

The radios used in Wi-Fi are not so different from the radios used in $5 walkie-talkies. They have the ability to transmit and receive. They have the ability to convert 1s and 0s into radio waves and then back into 1s and 0s. There are three big differences between Wi-Fi radios and walkie-talkies:

Wi-Fi radios that work with the 802.11b and 802.11g standards transmit at 2.4 GHz, while those that comply with the 802.11a standard transmit at 5 GHz. Normal walkie-talkies normally operate at 49 MHz. The higher frequency allows higher data rates.
Wi-Fi radios use much more efficient coding techniques that also contribute to the much higher data rates. For 802.11a and 802.11g, the technique is known as orthogonal frequency-division multiplexing (OFDM). For 802.11b, it is called complementary code keying (CCK).
The radios used for Wi-Fi have the ability to change frequencies. 802.11b cards can transmit directly on any of three bands, or they can split the available radio bandwidth into dozens of channels and frequency hop rapidly between them. The advantage of frequency hopping is that it is much more immune to interference and can allow dozens of Wi-Fi cards to talk simultaneously without interfering with each other.

Because they are transmitting at much higher frequencies than a walkie-talkie, and because of the encoding techniques, Wi-Fi radios can handle a lot more data per second. 802.11b can handle up to 11 megabits per second (although 7 megabits per second is more typical, and 802.11b may fall back as low as 1 or 2 megabits per second if there is a lot of interference). 802.11a and 802.11g can handle up to 54 megabits per second (although 30 megabits per second is more typical).

You might be wondering where the funny 802.11 nomenclature comes from. The Institute of Electrical and Electronics Engineers creates standards, and it numbers these standards in unique ways. The 802.11 standard covers wireless networks. The a, b and g notations identify different flavors of the 802.11 standard.

Fortunately, all of this radio technology is hidden in a Wi-Fi card and is completely invisible. Wi-Fi, in fact, is one of the easiest technologies that you will ever use.

Adding Wi-Fi To Computers

One of the best things about Wi-Fi is how simple it is. Many new laptops already come with a Wi-Fi card built in -- in many cases you don't have to do anything to start using Wi-Fi. It is also easy to add a Wi-Fi card to an older laptop or a desktop PC. Here's what you do:

Buy a 802.11a, 802.11b or 802.11g network card. For a laptop, this card will normally be a PCMCIA card that you slide into a slot on your laptop. Or you can buy a small external adapter and plug it into a USB port. For a desktop machine, you can buy a PCI card that you install inside the machine, or a small external adapter that you connect to the computer with a USB cable.
Install the card
Install the drivers for the card
Find an 802.11 hotspot
Access the hotspot

A hotspot is a connection point for a Wi-Fi network. It is a small box that is hardwired into the Internet. The box contains an 802.11 radio that can simultaneously talk to up to 100 or so 802.11 cards. There are many Wi-Fi hotspots now available in public places like restaurants, hotels, libraries and airports. You can also create your own hotspot in your home, as we will see in a later section.

To learn more about configuring your connection, setting up a network at home and how to keep your network secure, visit this article at HowStuffWorks.com.