The majority of households in the United States now have high definition televisions according to Nielsen.

The research firm says 56% of American households now own an HDTV making High Definition television one of the most quickly adopted consumer entertainment technologies of the past 20 years.

Interestingly, despite the fact that HD sets are now in more than half of all American households, Nielsen reports that HD viewing is still far eclipsed by viewing of standard definition television.

The research giant reports that only 13 percent of total day viewing on cable and 19 percent of viewing on broadcast television is “true HD” viewing, which requires an HD television and HD tuner that are tuned to an HD channel.

So, despite the billions of dollars spent on buying HDTVs, more than 80 percent of television viewing is still a standard definition experience.

There are three reasons why HD viewing is so low: first, 44 percent of homes either do not have an HD set or an HD service; Second, most HD homes have at least one non-HD TV set resulting in about one-third of programming being viewed on a standard set; Finally, even on HD sets, about 20 percent of viewing is to standard definition feeds.

Nielsen says the most watched type of programming in HD is sports programming with kids programming the least likely to be watched in HD.

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