Wi-Fi – definition and meaning

Wi-Fi is a facility that allows computers, laptops, smartphones, tablets, printers and other devices to communicate with one another or connect to the Internet wirelessly within a specific geographical area.

Put simply, it is a way of getting Internet without the wires. It allows several devices in one area to be connected at once, without having to install extra telephone lines or cables.

The term emerged in the 1990s from Wireless plus Fi, an apparently arbitrary second element, after Hi-Fi. It is often mistakenly interpreted as a short form of Wireless Fidelity.

As a verb, it means to adapt or convert to Wi-Fi compatibility, as in: “Central London plans to be completely Wi-Fied by the end of the decade.”

Wi-Fi in your homeThe benefits of Wi-Fi are obvious – a wireless connection to the Internet means that your devices are not tied to a fixed location in your home.

It is a technology for wireless LAN (local area network) with devices based on the IEEE 802.11 standards.

3g.co.uk has the following explanation for Wi-Fi:

“Wireless connectivity, often known as Wi-Fi, is the technology that allows a PC, laptop, mobile phone, or tablet device to connect at high speed to the internet without the need for a physical wired connection.”

“The technology uses radio signals to transmit information between your Wi-Fi enabled devices and the internet, allowing the device to receive information from the web in the same way that a radio or mobile phone receives sound.”



What do Wi-Fi and microwaves have in common?

Wi-Fi allows devices to connect at data transfer rates between 11 and 11 Mb/sec (megabits per second), compared to standard Ethernet’s 10 Mb/sec maximum via cables.

Wi-Fi operates using the same frequency used by mobile telephones and microwave ovens over 11 channels – 2.4 GHz (Gigahertz).

Many cafes, restaurants, airports, train stations, buses, trains, public buildings, and airplanes today have Wi-Fi installed.

If you see a fellow passenger on an airplane surfing the Internet on a laptop or smartphone, they are likely using the aircraft’s Wi-Fi network, especially if you are flying high up in the air.

Wi-Fi signsMost Wi-Fi signs have a dot with a series of curved lines, as you can see in the image above. For cafes and restaurants, they are definitely a crowd puller, just like Internet cafes used to be. However, as more and more people get Internet access on their smartphones, and can turn those into wireless HotSpots, the attraction is expected to wane.

How does Wi-Fi function?

Wi-fi creates a network in an area – your home, office, commercial premises – a small zone where devices can obtain broadband Internet.

It uses radio waves just like televisions, microwaves and mobile phones do. This zone is often referred to as a Wireless Local Area Network (WLAN).

A wireless transmitter – also known as a ‘hub’ – receives data from the Internet via, for example, your household’s broadband connection. This data is converted into a radio signal and is then emitted.



BBC WebWise writes:

“You could think of the transmitter as a mini radio station, broadcasting signals sent from the internet.”

“The ‘audience’ for these transmissions is the computer (or computers, as more than one can connect at the same time) which receives the radio signal via something called a wireless adapter.”

The whole process also works the other way round. Your device sends the data to the wireless transmitter, which converts it and sends it through your broadband connection.

All this is done incredibly rapidly. If you are having a voice-call or video-call conversation via WhatsApp or Skype with a friend on the other side of the world, you will not be aware of any delay in the transmission of data – your conversation proceeds smoothly and seamlessly, as if you were standing in front of each other.

Scientists at Eindhoven University of Technology in The Nertherlands have developed Wi-Fi that works on wavelengths of 1500 nanomeers and higher – i.e. infrared rays, which allow devices to communicate 100 times faster than our current system.

Video – How does Wi-Fi work?

Wi-Fi is pretty miraculous, this BBC Earth Lab video explains. Who would have thought a few decades ago that we would be able to send massive amounts of data through the air in our own homes, in the park, or on a bus?