apple tv show my screen
How do I set up Apple TV to show my computer screen
AppleTV 2
You need a mac that is mid 2011 or newer (early 2011 for MacBook Pro) running OSX 10.8 Mountain Lion or newer then set up home sharing and same apple id and you can mirror.
If you have PC or an older mac try a third party app called airparrot which will help you.
Jules