What is Wi-Fi and how does it work?

Author: Matt Powell

Last updated: 19 March 2024

Wi-Fi is a wireless networking technology that allows devices such as computers, tablets, game consoles, and smartphones to communicate without a physical link.

Rather than needing to be tethered to an Ethernet cable, you can simply connect over the air. This provides an easy way to network homes and access the internet without wires cluttering up the place.

In this guide, we’ll explain how Wi-Fi works and how you can use Wi-Fi at home and on the move to get connected without cables.
 

What does ‘Wi-Fi’ mean?

The term Wi-Fi isn’t short for anything. Though it was inspired by the audio term ‘Hi-Fi’, it doesn’t actually stand for ‘Wireless Fidelity'.

The name and logo were created for marketing purposes. It’s a trademarked name owned by the Wi-Fi Alliance, an organisation that certifies wireless networking equipment and promotes the use of the technology.

Wi-Fi is the official name, though it's also commonly spelt as ‘WiFi’.

Often you’ll see wireless-capable equipment boast that it's been certified by the Wi-Fi Alliance. This means it meets the standards for its certification process, and that suggests it has a good level of security or compatibility. But not all Wi-Fi hardware has been certified.

Typically, this is due to the cost of the certification process, and it’s not a sign that it’s incompatible with other Wi-Fi gear. So don't worry too much if you've got something missing the certification mark.

How does Wi-Fi work?

Wi-Fi transmits data using radio waves, mostly in the 2.4GHz-6GHz frequency range.

This radio signal allows devices to communicate wirelessly and means you don’t need a wired connection. So it’s very easy to get broadband and create a home network without having to worry about installing wires around your home.

The range of a Wi-Fi connection depends on the frequency, transmission power, and environment.

Using standard Wi-Fi devices, you can expect an indoor range of around 150ft for a 2.4GHz network, going up to around 300ft outdoors. But it’s possible to get a much longer range using directional antennas and more powerful transmitters.

• Wi-Fi frequencies and speeds - what is 802.11?

  Something you’ll come across when looking at wireless technology is the 802.11 specifications, and they need some explanation. You’ll need to understand what they mean if you want to get the most out of Wi-Fi. 

  These Wi-Fi standards are created by the Institute of Electrical and Electronics Engineers or the IEEE. The ins-and-outs of the IEEE standard technical details aren’t something most of us need to know. But it’s helpful to have a rough understanding, so you have an idea of the speeds you should be able to get on that device.

  In short, the newer the IEEE 802.11 standard a Wi-Fi device supports, the faster it can transfer data.

  The table below shows the top speeds of the most common Wi-Fi specifications. These are backwards compatible, so you can buy a cutting-edge high-speed 802.11ax router and still connect old hardware. Just make sure you consider the frequency your broadband is using too.

  802.11 standard	Wi-Fi version no.	Max speed	Frequency
  802.11b	Wi-Fi 1	11Mb	2.4GHz
  802.11a	Wi-Fi 2	54Mb	5GHz
  802.11g	Wi-Fi 3	54Mb	2.4GHz
  802.11n	Wi-Fi 4	300Mb (5GHz)	2.4 / 5GHz
  802.11ac	Wi-Fi 5	7Gb	5GHz
  802.11ax	Wi-Fi 6	10GBb	2.4GHz & 5GHz

  Remember that these are only theoretical maximums, particularly the 802.11ac and 802.11ax ranges. Though they can reach top speeds in ideal conditions, the reality is that the actual speed will be much lower. Fortunately, these are still faster than older tech, so it can be worth investing in a new router.

  You can also get better speeds using features such as 'beamforming' and 'MIMO', but this may require some configuration and experimentation to get right.

  Also included in the table are the Wi-Fi version numbers. These have been recently introduced as a friendlier alternative to the 802.11 labels. This is a new initiative though, so there will be lots of devices sticking to the old naming convention still. It definitely still helps to know what each of the IEEE numbers means.

  The table also shows Wi-Fi network frequencies.

  Many devices only utilise the 2.4GHz frequency band, which provides greater range and penetration of obstacles like the walls of your home. But it is more prone to interference as it’s the same frequency used for cordless telephones and other devices.

  The 5GHz band is supported by newer 802.11n routers, as well as the old 802.11a. It can definitely be much faster but it also has a shorter range.

  When buying Wi-Fi hardware, you should check that the supported frequencies match your existing Wi-Fi setup. But to simplify things, we’d recommend always going for ‘dual-band’ or 'tri-band' equipment as it will then support both 2.4GHz and 5GHz. Not only is this better from a compatibility point of view, but it also means you can switch to using 2.4GHz if the limited range of 5GHz proves to be a problem.

How to set up Wi-Fi

Setting up Wi-Fi access at home is simple. All you need is a Wi-Fi router, which is the key bit of hardware that generates a wireless network. Your broadband provider will usually supply one for free, or you can purchase your own router. 

In brief, here are the steps to setting up Wi-Fi for the first time with a new router: 

1. Hook up your Wi-Fi router by connecting it to the power and broadband connection with the provided wires.
2. Wait for the Wi-Fi network to come online. This can take a couple of minutes and will usually be indicated by a green light on the router.
3. Using a Wi-Fi device, such as a laptop or smartphone, scan for the Wi-Fi network. The default network name will be shown in the router manual or on a sticker attached to the router.
4. Select the Wi-Fi network and enter the password supplied with the router.

You should now be connected to Wi-Fi!

• Which broadband provider has the best free Wi-Fi router?

  The quality of ISP-supplied routers varies. Some will update their kit regularly, while others may go years without changing the hardware. So those can be a little outdated by modern standards. 

  To find out more about what kind of router each provider uses, you can read more about them in our router round-ups:

  • BT router round-up
  • TalkTalk router round-up
  • Virgin Media router round-up
  • Sky Broadband router round-up
  • Plusnet router round-up
  • Vodafone router round-up
  • NOW Broadband router round-up

Wi-Fi router security and customisation

After you’ve set it up for the first time and confirmed everything works, there are some additional changes you can make to your wireless local area network, or WLAN. You can do so by accessing the router’s administration panel, which will improve your security and deter potential hackers.

Instructions for this will be given in the user manual, but generally, try using a web browser to connect to the router's IP address.

Change the admin password

If your router has a default admin password, which is often simply ‘admin’, then it’s very important to change this to a strong passphrase as a Wi-Fi security priority.

Some routers don’t have a password but will prompt you to create one when logging in for the first time instead.

Change the network name and password

You can customise the Wi-Fi network name too. This is called the SSID or 'Service Set Identifier'. It doesn’t have to be left on the default setting. It can be changed to anything you like!

This is helpful if there are lots of networks in your area with similar names. The Wi-Fi password can also be changed here. 

Set up a guest network

Some routers offer a guest network feature. This is a segment of your Wi-Fi network with its own name and password, so visitors can get online without giving away your main Wi-Fi login. It also prevents them from accessing any shared devices, such as hard drives or printers, on your network.

Create a dual-band network

If your router uses both 2.4GHz and 5GHz frequencies, you can have them running simultaneously. That way, you get the fastest Wi-Fi speeds while still supporting older devices and benefitting from the coverage of a 2.4GHz network. 5GHz is faster but has a shorter range, and the signal is more likely to be blocked by the walls of your home.

For more help with configuring your router, read our in-depth guide to changing router settings.

Frequently Asked Questions about Wi-Fi

• What devices use Wi-Fi?

  Wi-Fi is used by a huge range of wireless devices: smartphones, tablets, game consoles, computers, cameras, and smart home gadgets. If it needs internet access, then it’s probably a Wi-Fi-enabled device.

  To find out if a device supports Wi-Fi, check the specifications or look for the Wi-Fi symbol.

• Can you get Wi-Fi for free?

  Free wireless internet hotspots can be found all over the world. These public Wi-Fi networks are common in coffee shops, pubs, restaurants and hotels, but you may also find them in your local bank or barber.

  Check out our guide to Wi-Fi hotspots to learn more about free Wi-Fi and how to find it.

• What is a mobile Wi-Fi hotspot?

  A Wi-Fi dongle, or mobile hotspot, is a mobile broadband dongle which creates a Wi-Fi network to share its mobile internet connection. This lets you get mobile broadband access on any Wi-Fi device.

  Your mobile phone can often be used as a hotspot, so if you need internet on the go? You can usually connect through your phone.

• What is an access point?

  A Wireless Access Point, sometimes known as WAP, or just AP, is a device which connects to a wired network in order to provide wireless connectivity to that network in the local area.

  These are typically used by organisations where it’s necessary to support a very large number of users over a big area. At home, we can just use a Wi-Fi router, which is a hub that provides wired and wireless networking and internet access in one device.

• How can I improve a weak Wi-Fi signal?

  For the best coverage, your Wi-Fi router should be placed in a central position in your home, away from walls and anything which could interfere with the wireless signal, such as cordless phones or fridges. You should use a 2.4GHz network for the best signal range.

  You can use a Wi-Fi signal booster to provide coverage in areas where the Wi-Fi is weak or non-existent.

Expert Summary

Wi-Fi is a handy technology that means that you don’t need to worry about messy wires and can connect multiple devices to the internet anywhere in your home.

Most of us probably already use Wi-Fi, but we may not have taken the time to learn much about it beyond the password. But it’s definitely worth getting up to speed in order to improve security and get more from your Wi-Fi.

There are plenty of things you can do to make your router better. You can easily change the SSID and password yourself to make it more secure, and by simply moving where you keep it, you can make the signal better in your home. If not, you can look into either buying a Wi-Fi signal booster or even buying a new router yourself. Just make sure your provider allows for that.

If your broadband still isn’t fast enough, don’t worry. You can always switch providers. Use our deals checker to see what providers are offering in your area.

Want to be a whizz at Wi-Fi? Why not read our guide to wireless broadband?