What is a modem?

A modem is a device used to connect a home network to the internet. Modems are essential in connectting devices such as phones, computers and tablets to the internet, by converting digital data from your device into analogue signals that can travel over phone lines, cables and satellite connections. Modems also perform the reverse function - converting incoming analogue signals back into digital data that your device can understand. 

Modems usually work in conjunction with routers in home networks, where the modem acts as the bridge to connect the wider internet through your internet service provider (ISP), and the router then distributes that connection to various devices either wirelessly or through Ethernet cables. 

You can think about it like a motorway; the modem acts like a slip-road, a point where vehicles (data) can enter or exist the motorway (the internet). The router, on the other hand, is like a traffic light system, managing the flow of cars (data) between various destinations (your connected devices) in your home.