Routing is the process of moving data packets from one network to another. Think of it as the GPS for internet traffic—routers determine the best path for data to travel from source to destination.
Each router maintains a routing table, which contains information about available paths. When a packet arrives, the router checks the destination IP address and looks up the best match in its table. If no direct match exists, the router uses a default route, often pointing to another router that knows more about the network.
Routers communicate with each other using routing protocols like OSPF or BGP to exchange information about network topology, ensuring paths stay up-to-date even if links fail.
In essence, routing enables devices on different networks to communicate seamlessly, making the internet work as a single connected system.