The term "high-definition" was almost a curse five years ago, when politicians, broadcasters and TV makers were reluctant to hoist massive changes upon the nation's television landscape.

Suddenly the same term — originally meant to describe greater density in TV displays — is being used to tout all kinds of products.

Skin creams. Sunglasses. Laminate counter tops. There's even "Starting High Definition Churches" — a book with guidance on building an HD church with "improved clarity" and "higher resolution."

The new worshipful aura of HD brings a laugh to Dale Cripps, the founder of HDTV Magazine. But the HDTV evangelist quickly turns serious.

As the United States marches from analog TV toward the full glory of digital TV, consumers have to wade through hype, linguistic imprecision and a new foreign language.

Market research shows many people are downright confused, which isn't ideal when they're spending $2,000 or more on a new TV.

"Right now people are buying the devices and they don't have all the information," Cripps says. "It's a huge problem."

About 15.7 million households had HDTV sets by the end of 2005, with 50 million predicted by 2009, according to Forrester Research.

The brisk adoption is a consumer-electronics industry coup, considering how the digital TV format had been introduced only in 1998, thrusting dozens of new technological terms like "aspect ratio," "720p," or "1080i" at consumers, who also must evaluate different kinds of digital TV displays, like plasma, LCD or DLP.

By comparison, it took color TVs a decade to get into just 5 million households during the transition from black-and-white boob tubes.

But the HDTV coup also points to failures in consumer education.

Forrester estimates about half of HDTV owners are not subscribing to an HDTV service through their existing cable or satellite TV accounts.

That means some of them are watching the same old standard TV broadcasts on their expensive new TVs, missing the boat for the truly eye-popping images that digital HD programming offers.

What they're seeing on their screens might not look any better than the programming they used to watch, and in some cases, might actually look worse because imperfections would be more visible on the bigger, sharper digital displays.

HDTV delivers images about five times as detailed as standard TV. Beads of sweat are crystalline on athletes' faces. Blades of grass are vivid. And you could pick out grains of real snow — not the TV snow of poor reception.

Forrester estimates at least 4 million households mistakenly assume they're getting high-definition pictures. Those are regular analog cable subscribers who say they're getting HDTV service from their cable operators — which is impossible, since HDTV service comes only with digital cable.

Getting HDTV goes beyond buying an HDTV set and plugging it in.

You must also have equipment to access HD content. For cable or satellite TV subscribers, that means getting an HD receiver set-top-box or CableCARD, which slides into some newer HDTV models. A subscription to the operator's HDTV offerings is typically required, which sometimes cost extra.

Some HD programming is also available via free, over-the-air television broadcasts by the major TV networks. Doing so usually requires mounting an antenna on the roof.

Some cable and satellite operators negate the need for the antenna by offering so-called terrestrial TV receivers in their set-top boxes, allowing them to relay local HD broadcasts to their customers.

Several years ago, retailers notoriously botched HDTV demonstrations by not piping HD content into the shiny new displays.

Today, analysts say most stores have wised up and are showing off real high-def images on HD screens. But in many cases, consumers go home assuming they'll get the same level of performance without knowing they have to take additional steps to get HD video onto their screens.

"The retailers are trying, but the hard part is that you have to explain to people that spending $2,500 on the set is just the beginning and now you're going to probably have to spend more money every month," said Forrester analyst Josh Bernoff.

There's another often-overlooked piece of the HDTV puzzle: cable inputs. Using the right connectors between a TV set and a cable or satellite box will also affect whether the image you see on the screen fully captures HD resolution, which ranges from 1 million to 2 million pixels.

If you're using S-video or component cables, which send analog signals, then the HDTV digital image is forced to go through more conversions, possibly degrading the picture.

Experts recommend HDMI cables. HDMI sends high-definition signals and is also becoming more of a standard input on HDTV sets. Before 2005, only higher-end models had HDMI inputs, but most any new HDTV model will have them, said Shyam Nagrani, a digital video analyst at iSuppli Corp.

Bear in mind, too, that only some TV programming is available in HD, though the list keeps growing. A preliminary tally of HD programming by HDTV Magazine showed about 650 hours of HD content will be available on any given day next week, roughly a 30 percent increase from last year.

The total didn't include the Feb. 1 launch of VOOM — 15 new channels of round-the-clock high-definition programming distributed chiefly through Echostar Communications Corp.'s Dish satellite network.

With the exception of reality TV series, most prime-time and late-night shows by the major networks are now broadcast in HD. Most major sports, including the upcoming Olympics, are in HD. Cable and satellite networks such as ESPN, HBO, Showtime, CineMAX, Discovery, HDNet and National Geographic also offer high-definition channels.

For a television-hungry population, that's still not enough, and access will depend on the channels you get from your cable or satellite TV operator, which vary from location to location.

More is on the way. For instance, Dish plans to increase its HD channels from 25 to 35 by the end of the year, while DirecTV promises the capacity to deliver 150 national HD channels and 1,500 local HD channels by 2007.

Comcast Corp., the nation's largest cable operator, offers between 10 and 15 HD channels in most of its markets. Now Comcast is starting to introduce video-on-demand services in high-definition.

For Cripps, of HDTV Magazine, copious HDTV programming will make the technology more than worth the hype.

"If creating warm and good memories is part of the benefits of a good culture, we're going to get that here with better pictures penetrating people's minds," he said. "And that's why I think we have a better world coming."