While some television sets can come with an HDTV receiver built in, this feature would be aptly advertised. So if you don't know for sure, there's a good chance it likely doesn't.
So assuming you don't have a built in tuner, you will need a receiver from either the cable company or Directv (or some third parties). You can even get a tuner for "over the air" HD signal. Each one with their own pro's and con's. And yes, you'll only be able to watch channels that broadcast in HD signal. However you'll should be able to watch regular broadcast channels as well (depending on your service plan). The number of channels broadcasting in HD is slowly growing (and a point of sale for the different cable/sat providers). The February 17 (2009) DTV transition should help bring more HD programs at a quicker pace.



