I bought an HDTV. When I turn it on, I’m watching in HD, right?
Maybe, but not usually. You must be able to receive an HD signal.
This can be done many ways; the most common are from your cable/satellite providers.
If you have a television with a digital tuner (sometimes referred to as an integrated DTV), you can watch free over-the-air digital broadcasts with the aid of a rooftop antenna or “rabbit ears” connected to the set.
Note: If you have a DTV monitor, you will need a digital or HD set-top box connected between the antenna and the monitor to receive and display over-the-air digital or HD programming. Confirm with your retailer that the set-top box is compatible with your monitor.