Which computer network component connects two different networks together and allows them to communicate?

A router.

Explanation:

A router is a device that operates in layer three of level 3. Thus, it allows several networks or computers to connect to each other and, for example, share the same Internet connection.

A router uses a routing protocol, which allows it to communicate with other routers and share information with each other to determine the fastest and most suitable route to send data.

answer ingenuity;