The main purpose of a router in a home network is to connect multiple devices to the internet and to one another. Routers manage data traffic between devices, ensuring effective communication and resource sharing within the network. They also provide essential security features such as firewall protection and network monitoring. By assigning IP addresses to devices, routers facilitate the management of connections, allowing seamless access to the internet. This central role makes routers indispensable for any home or office network setup.