If you have an Apple TV, you can watch videos in your iTunes library on your home theater system. 

These videos must be compatible with Apple TV. If you drag a video file from the Finder to the iTunes window and the video doesn’t appear in iTunes, it isn’t compatible. In some cases, you can save video files in a different format so that they work with iTunes.

Any video that plays on iPod, iPhone, or iPad is compatible with Apple TV.

Here are ways to save a version of a video to work with iTunes and Apple TV:

For more information, see the Apple TV user’s guide at the Apple TV Support website.