Which device is responsible for connecting multiple networks together?

The device that connects multiple networks together is a gateway. A gateway serves as a crucial point in networking as it enables communication between different networks, often with varying protocols. It translates the communication protocols between the networks, allowing devices from one network to communicate with devices on another network effectively. This is particularly important in scenarios where you have a local area network (LAN) that needs to connect to a wide area network (WAN) or the internet.

In contrast, a hub is a basic networking device that connects multiple devices within the same network segment but does not facilitate inter-network communication. A switch, while more advanced than a hub, operates at the data link layer and primarily connects devices within the same network, managing data traffic through MAC addresses without handling different network layers. An access point, on the other hand, provides wireless connectivity to a network but does not itself connect multiple distinct networks together. Therefore, the gateway is the essential device that enables connectivity and communication between different networks.