How to use AirPlay with a Mac

AirPlay allows two Apple devices to share the same screen, and it can be used for a number of things. For example, if you download a movie on your Mac, but want to watch it on your Apple TV, AirPlay will sync those two devices. Likewise, if you want to play a video on your Mac, but only have it on your iPhone, you can use AirPlay and watch it on a bigger screen. In…