You've noticed something that many have over the years. DVD playback on PC/Mac was superior to what you saw on the SD TV (480).
And that was with what DVD (non-HD) content we had then.
Hope this helps,
But HDTV is not all about resolution, it's also has many features to help with Digital Rights Management and more. I think if you read the Wikipedia articles you can catch up.
Bob
HD resolution has 720 or 1080 lines of resolution. The 24" iMac has more than that. So does that mean that when I watch a HD clip, it is in true HD just like the HDTVs nowadays? If I get a blu ray drive or something and try to watch a movie on an iMac then is it true complete HD? Or is there some sort of other technology in the HDTVs that makes them different?

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