Hi-Def is just like the sensation of finally getting up the courage to walk in on that Advanced Calculus class you've slept through for three months. If you can wade through all the random combinations of letters and numbers like 720p and 1080i, you'll find that there are some fantastic deals to be had right now, thanks mostly to improving technology and competition. Ready to make the jump to the vivid world of high-definition, or just want to know what the heck all those geeks and salespeople are talking about? Read on.

First off, let's tackle what High-Definition means. A television works by painting an image over and over again, usually around 60 times per second. If half the image's lines are repainted every time the screen refreshes, it's called an interlaced scan technique. If the entire picture is repainted every time the screen refreshes, it's a progressive scan technique. A regular television displays a picture that's made of 480 lines from the screen's top to bottom. The high-definition threshold begins when the number of lines shoots up to 720, packing in more detail for those sharp "I-can-actually-see-the-guy's-skin-pores!" details. Right now, the zenith of high-definition capability you can buy is 1080p-1080 lines, progressive scan.. Critical viewers prefer progressive scan for its smoother look when watching content that packs a lot of motion (like sports), mainly due to the fact that you're seeing twice the amount of pictures per second (framerate) as you'd get with interlaced scan. The only problem is, unless you're playing a game on a PS3 or feeding content through a high-end video card on your PC, there is no actual 1080p content available for your tv. Weird, huh? High-definition cable is piped in at 1080i and high-definition movies are filmed at less than half the rate your screen is repainted at (24 frames-per-second)...and neither of those standards are likely to change anytime soon. Having said that, if you can still find a 1080i tv (1080 lines, interlaced scan) or you pick up a 720p model (720 lines, progressive scan), you'll be satisfied. As a matter of fact, it can be difficult to discern the additional detail differences between a 1080p unit and a 720p when viewing a screen size less than 50" (in the right viewing ranges). Beyond upping the detail you see, true high definition sources also deliver a larger picture, pumping out images that fill your screen at the 16:9 "widescreen" aspect ratio. In contrast, the aspect ratio of DVD content is 4:3.

Now that you've got a grip on what HD is, the next challenge is finding how you want it served up in your home. Price and size are the two biggest deciders for most people. Bigger isn't always better. Sitting too close to a large screen reduces the quality of the image you'll see. A general rule of thumb is to multiply your screen's size by 2-3 times to determine the best distance to view it from. For example, if you're watching a screen that's 32 inches large, set up your seating to be around a minimum of 5' 4" and maximium of 8' away from the screen. Once you've figured out your size range and whether you want to make a more economical purchase or stretch the budget to "DANGER!" territory, you'll find that choosing your new setup is pretty simple.

One more factor that will further narrow down your list is knowing what source will be supplying your tv with it's high-definition goodness. If you're planning on hitching your tv to your cable box, you're really not going to need to shell out the extra money for a unit with a built-in digital tuner. Try finding a tv that's labeled "HDTV monitor" or "HDTV ready"...it will still be able to do perfect justice to whatever high-definition source it's being fed.

Now you're ready to make a short-list of best options you find. You can scrutinize the refresh rates of LCDs, compare weights and bulkiness of tube tvs or see which plasma models will connect to your pc, or just be lazy and check out our suggestions. Here they are:

Around 30" screen size for less than $1000
Samsung's bargain-priced 27" Slim Fit Tube HDTV trades off some of the classic bulk and weight of a tube tv (yes, the same technology as the standard-definition tv's you grew up with) and keeps the its classic advantages. An excellent contrast ratio, resolution, color saturation and color accuracy have always been strengths of CRT tv's while older models of plasma and LCD were struggling to produce a deep, real black and the contrast to distinguish what's going on in dark movie sequences. Samsung's tube is light on features, but will deliver great images in 1080i for under $600.

Samsung's LN32A450 is a great choice if you're looking for a smaller set that exudes flat-panel sexiness. LCDs typically serve up images with a lot of dynamic "pop" in their colors, as opposed to the more natural colors of plasma...you should see them both in action to see which is more appealing. Typical disadvantages of LCDs include the screen's tendency to fade when viewed from extreme angles and the possibility of seeing blur in fast action (particularly in gaming or watching sports). Samsung's 32-inch LCD boasts great native 720p image quality and minimizes the blur factor with a 6-millisecond response time (the amount of time it takes for a pixel to go from white to black and back again), far faster than the 15-millisecond threshold it takes to typically start noticing blur. Features like three HDMI inputs, a USB port for an easy way to showcase your own photos and music and many different ways to adjust picture quality sweeten the proposition for $750-$850.

Around 40" screen size for less than $3000
Samsung's LN40A650 boasts all of the features of its kid brother mentioned above, but ups the resolution to 1080p and adds a 120MHz refresh rate, along with an "Auto Motion Plus" video processing mode to further smooth things out in action sequences. There's even an Ethernet port for so your tv can add your favorite stock, weather and news selections to whatever you're viewing. Available for around $1500-$2300.

Panasonic's TH-46PZ85U, part of their Viera series, brings some of plasma's strengths to a smaller size. Plasma screens also boast small and thin form factors, and, as mentioned above, they also boast more natural colors. A typical disadvantage of plasma display is the possibility of seeing the ghost of an image that was left static on the screen at a bright resolution for a period of time (hours, not minutes). This is called burn-in.. The TH-46PZ85U lives up to plasma's great ability to produce deep blacks, serves up good picture quality and features a couple of tools to prevent, and fix, burn-in. Two HDMI inputs, a PC input and an SD card slot for personal media is included, all for around $1500-$2200.

50" and over screen size for less than $3500
Check out the Panasonic TH-50PZ800U. The TH-46PZ85U's 50-inch-large big brother touts all the same strengths, but adds touches like a THX picture mode that automatically calibrates the unit's image adjustments to THX specifications for stunning results. It retails for around $3000. Samsung's LN52A650 expands all the LN40A650's features in a 52-inch large piece of real estate. It's available for $2200-$3700.

If you're looking for a more affordable way to get into the 55" and over range, there are some bargains to be had in rear-projection televisions. These units satisfy with sheer size and almost always stay under $2000, but tend to get washed out by light in bright rooms, need periodic bulb changes and often will wash out at extreme viewing angles like some LCD units. If these sacrifices sound okay to you, then we'll skip rear-projection and recommend a personal favorite, Panasonic's PT-AE2000U. After all, why have 55" when you can have 100" for almost the same price? The PT-AE2000U is a native 1080p projector that can handle all the same sources as the tvs listed above, but will deliver outstanding blacks, excellent color saturation and is bright enough to compete with ambient light in your room. Its price ranges from between $2600-$4000, which isn't bad considering you have an image from 39 feet to 200 feet large, if your space allows.

The most important thing to remember is that you need to make sure you use high-definition connections for all the sources that will be feeding into your new set. If you're not connecting with HDMI or high-definition component cables, you'll experience the same quality you did back in the 90's. Speaking of the 90's, now's the time to upgrade to an upconverting DVD player...it won't give your movies the same stellar quality of native high-definition content, but it will make them look a lot better. It also doesn't hurt to have a technician configure your new tv's display settings to optimize the image, or at least play with the settings to find what you like.