Modems connect to the internet. Wifi, pronounced ‘why-fy’ enables you to connect to a modem without the use of wires. It uses low powered radio waves in the same way that your radio or television does. This means that you can use your laptop or other internet-enabled device anywhere in a building without having to install extra cables or phone lines, as long as the radio waves can reach the modem and it allows you to connect to it..
Wifi also allows several computers, laptops, printers and the like to be connected at any one time, essentially creating a network between all the devices in your home or office. Wifi is also increasingly found in public places, such as libraries and cafés, making it easy to access the internet while on the move, often for free.
Here is a BBC guide which will help you set-up Wi-Fi.
Why not read our other guides below such as what is a router or what is broadband?