Which device directs data packets to their destinations, forming the backbone of the Internet?

The router is responsible for directing data packets to their appropriate destinations across the internet and other networks. It operates by examining the destination address contained in each packet and determining the most efficient path for it to take through the network. Routers interconnect multiple networks and facilitate communication between devices that may be located on different segments of a network or separated by wide geographic distances. This function is crucial for the overall operation of the Internet, as it ensures that data can efficiently reach its intended endpoint, regardless of where that endpoint is located.

In contrast, a bus is a communication system that transfers data between components inside a computer or between computers but does not route packets between networks. A switch connects devices within the same network but does not perform routing functions between different networks like a router does. A server, on the other hand, provides services or resources to other computers but does not have the functionality to direct data packets across different networks. Each of these alternatives serves important roles in networking, but the router is specifically designed to handle the task of directing packets across the vast infrastructure of the Internet.