Routers and switches differ in networking by serving distinct functions. A router connects multiple networks and directs data packets between them, ensuring that data reaches its destination using the most efficient path. It operates at the network layer of the OSI model. In contrast, a switch connects devices within a single network, allowing them to communicate with one another by forwarding data packets based on MAC addresses. Switches operate at the data link layer and enhance local network efficiency, while routers facilitate communication between different networks.