High definition (HD) is no longer the future. It's here. With a proliferation of options, it's frustrating for consumers to make sense of it all. HD, HDV, AVCHD... what does it all mean? Here's a summary of terminology and choices.

What is HD?

HD video is a higher resolution than the previous format, standard definition (SD). Camcorders that record SD video produce a resolution of 640 x 480. That means 640 lines of vertical resolution and 480 lines of horizontal resolution. In recent years, widescreen, or 16:9, became more common. This has a slightly larger resolution of 720 x 480.

There are two competing HD formats available in consumer camcorders right now: 720p and 1080i.

The first, 720p, refers to camcorders producing a resolution of 1280 x 720.

The second, 1080i, refers to camcorders producing a resolution of 1920 x 1080.

That's easy to understand, right? 1080i has a higher resolution. If these were digital still cameras we were talking about, that would be the end of the argument. But video incorporates motion. This is where the issue of the "i" and the "p" comes into play. The "i" stands for interlaced. Traditionally, camcorders split up those horizontal rows of resolution into odds and evens. First one set is refreshed, then the other set. Each of these "fields" is refreshed, back and forth, each at 30 times per second. It happens fast enough that the human eye usually can't see the slight lag time. However, when you pause a interlaced video clip, you'll see a distinct jagginess.

The "p" in 720p stands for progressive. This means that the entire image is refreshed at the same time, 30 times per second. Qualitatively, this tends to produce smoother motion, and is often preferred for sports shooting, because freeze frames will not have the same jagginess that 1080i produces. The trade-off is that 720p has less resolution.

Note: 1080p is another term popular in for televisions. As you might have guessed, it means 1920 x 1080 progressive. Lots of TVs can support it for playback, but currently very few consumer camcorders actually record in 1080p.

The Difference between Media and Format

This is the most common area of confusion. The term "format" typically refers to the compression the camcorder uses. These result is various file types that can be read by your computer. "Media" refers to the physical medium onto which video is stored. Some camcorders have multiple media, but it's rare that a camcorder has more than one format. These terms are sometimes used interchangeably, only adding to the confusion. For this very reason, it's even hard for us to organize categories on CamcorderInfo.com. Here's what you need to know:

Common Media Types

Flash Memory (aka Solid State, Memory Card) - Flash memory is a catch-all term for any media that have no moving parts - no spinning discs or tape reels. Many consider this the media type of the future. Battery efficient, extremely compact, and easy. Capacities may be limited compared to HDD, though it gets larger every year. Some camcorders have removable memory cards, some have non-removable internal memory, and some have both. Popular models: Canon HF10, Canon HF100, Panasonic HDC-SD9, Sony HDR-CX7, Samsung SC-HMX20, Sanyo VPC-HD1000

Hard Disk Drive (HDD) - HDD media is high capacity, usually 60 - 120 gigabytes. Long record times are great, but you must have the discipline to routinely back up video to a separate hard drive or DVD. Popular models: JVC GZ-HD7 and GZ-HD6, Canon HG10, Sony HDR-SR12, Panasonic HDC-HS9

Tape - Some HD camcorders use a type of tape called MiniDV. These are exactly the same tapes used by standard definition DV camcorders for years. Tape is definitely old school by most standards. You have to fast forward and rewind, just like on your VCR. Reliable, widely available, and fairly sturdy. Popular models: Canon HV20, Canon HV30, Sony HDR-HC9

DVD - In camcorders, this always refers to the smaller, 8cm "miniDVD" discs. DVD is convenient because it's familiar to so many of us. However, the record times can be as little as 15 minutes when shooting in the highest quality. Be warned that you cannot take DVDs from your HD camcorder and play them in your home DVD player unless you have a Blu-Ray player. Popular models: Sony HDR-UX10 and HDR-UX20, Canon HR10

Common Formats

AVCHD - Introduced in 2006, AVCHD has exploded in popularity, allowing HD video to be recorded onto all the non-tape media listed above. AVCHD has gotten a little better each year. Some models are finally on par with HDV in overall picture quality. The format is expected to phase out HDV in the coming years. Every manufacturer has a slightly different recipe for AVCHD, so finding a compatible editing program can be tough. Also, you'll need a powerhouse computer to work with files. All current AVCHD camcorders record in 1080i, though the format allows for 720p. Popular models: Canon HF10, Panasonic HDC-SD9, Sony HDR-SR12

HDV - This is the oldest consumer high definition format. Today's consumer HDV camcorders only record in 1440 x 1080, then stretch the footage to 1920 x 1080 for playback. Camcorders compressing in HDV only record to MiniDV tape. Widely compatible with editing software and easy to use. Popular models: Canon HV20, Canon HV30, Sony HDR-HC9

AVC/H.264 MPEG-4 - No, it doesn't roll off the tongue. This format is currently used by some Samsung and Sanyo camcorders, all of which record in 720p. Popular models: Samsung SC-HMX10 and SC-HMX20, Sanyo VPC-HD1000

MPEG-2 Transport Stream - JVC is the only manufacturer using this format, found on its line of high definition Everio camcorders. On average, the lowest overall picture quality, now that AVCHD has matured. Low compatibility with editing software. Popular models: JVC Everio GZ-HD7 and GZ-HD6

Editing Your HD Movie

Every format/media combination is going to have it's own unique editing workflow, so there's no way to cover it all here. The take away points are pretty simple.

Tape-based HDV is still the easiest, simply because it's been around the longest. Footage must be transferred in realtime to you computer: 60 minutes recorded video means 60 minutes to transfer. Once it's on there, most editing software can work with the files just fine. You'll need a relatively new or powerful computer.

All the non-tape media have the advantage of speedy transfer from camcorder to a computer via USB. Once the files are in, however, the process can slow down. AVCHD is newer, and there's still a lot of compatibility issues. One program will work with Sony but not Canon and Panasonic. Some might do the reverse. Also, you'll need a very powerful computer to keep the programs from slowing or crashing entirely.

Then there's the issue of sharing your edited movies with friends and family. The most viable method of distributing HD movies is to burn them onto Blu-ray discs. Don't have a Blu-ray burner? No kidding, almost no one does. Until a cheap distribution system becomes available, your best bet is to shoot in HD, edit in HD, and save it. Then export a second copy that is downconverted to standard definition. That way you can burn it to a regular DVD or put it on the web. In a few years, you can re-export the movie in its original HD.

Is Now the Time to Buy HD?

If you're shopping for a new camcorder right now, HD is strongly suggested. In a few years, HD will be the standard for recording and displaying all types of video. Of course, there are still a lot of good standard definition camcorders out there, but they won't look as good when blown up on your big screen TV. Shooting in HD now means that you're future-proofing your memories for as long as HD exists. (Oh yes, HD will eventually be replaced by something even better, but we don't expect that for quite some time.) Shop smart, and shop comparatively to get the right camcorder for you.