Imagine you have a toy box (that's like your house), and inside that toy box you have lots of different toys (that's like all your devices, such as your phone, tablet, and computer). Now, imagine you have a special box (that's like the BT Home Hub) that helps all your toys (devices) talk to each other so they can work together and you can play with them all at the same time.
The BT Home Hub is a clever little box that sits in your house and helps your toys (devices) connect to the Internet so you can watch videos, play games, and do lots of fun stuff on them. It does this by sending out Wi-Fi signals (like magic radio waves) that your toys (devices) can catch and use to talk to each other and to the Internet.
The BT Home Hub also helps to keep your toys (devices) safe by putting up a special fence (that's like a security wall) around your toy box (house) to stop any bad guys from getting in and making a mess of your toys (devices). It also has a password (like a secret code) that you need to know to use it, so only you and your family can connect your toys (devices) to it.
So, in summary, the BT Home Hub is a special box that helps all your toys (devices) talk to each other and connect to the Internet, while also keeping them safe from any bad guys.