What is an Android TV device? Is that distinct from the FireTV? I plug my FireTV Cube into my projector. It has some kind of smart TV functionality and a secon

What is an Android TV device? Is that distinct from the FireTV? I plug my FireTV Cube into my projector. It has some kind of smart TV functionality and a second remote to go with it, but it's on a dongle and I don't plug it in because I don't use it.