HOW CAN I WATCH MY MAC AIR IN MY APPLE TV

Welcome to the Apple Community.

AirPlay Mirroring requires a second-generation Apple TV or later, OS X 10.8 or better and is supported on the following Mac models: iMac (Mid 2011 or newer), Mac mini (Mid 2011 or newer), MacBook Air (Mid 2011 or newer), and MacBook Pro (Early 2011 or newer).

Look under the Apple menu and 'About this Mac' and see what type of Mac you have and what OS you are using.

the question is if we have the right computer, how do we make it work? I want to watch something that is streaming on my computer, on my apple TV.

Read

http://support.apple.com/kb/ht5404

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