So you're in the market for your first digital camera. Your options are endless. Four or 5 megapixels? Optical or digital zoom? Point-and-shoot or SLR?

One of the main appeals of digital photography is instant gratification. You get to see images immediately, and you don't have to pay for film developing.

More than 100 million digital cameras have been sold in the past two years. This year's models include some as slim as a credit card with zooms so powerful you can almost zero in on action across town. Many allow you to make short video clips that look great on TV.

New buyers of digital cameras tend to favor simple point-and-shoots.

The most popular ones this year are ultraslender. They include the Fujifilm FinePix Z1, Nikon CoolPix S1 and Canon PowerShot SD400, which all sell in the $300 range.

Some point-and-shoot cameras tout their expanded zoom capability. The larger, thicker models won't fit in your pocket, but they can really zero in on what you're trying to capture.

These cameras, like Sony's $500 Cyber-shot DSC-H1, Konica Minolta's $400 DiMage Z6, Panasonic's $560 Lumix DMC-FZ30K and Canon's $450 PowerShot S2 IS, have 12X optical zooms — a huge jump from the more standard 3X zoom.

At full power, a digital camera's 12X zoom is equivalent to a 35mm camera's 420mm lens, like the huge lenses the pros use at football games.

Kodak and Nikon offer models with built-in wireless Internet capability. You can transfer pictures just seconds after they're shot. Kodak's new 4-megapixel EasyShare One can be found for around $500.

There are a couple of drawbacks: the Wi-Fi card that comes with the camera sucks the life out of the battery, and you can't actually e-mail a picture. You have to transfer it to Kodak's EasyShare Gallery Web site and send links to friends to view the image.

Nikon's CoolPix 8-megapixel P1 (around $400) and 5-megapixel P2 (around $300) don't need the additional Wi-Fi card. But you can't use the cameras in Wi-Fi cafes, only as part of your home wireless network. Once you've programmed the camera to be part of the network, you can zap the pictures out as fast as you can shoot them.

The professional-style camera — favored for sharper portraits and stopping action on a dime — has struck a chord with the public. Manufacturers have responded by cutting prices and introducing new models.

Canon's EOS Digital Rebel XT and Nikon's D70s are usually discounted to less than $1,000. But with rebates and holiday specials, both can be picked up for around $700 (the Nikon) and $800 (for the Canon) now.

Not exactly cheap, yet the cameras are selling as quickly as manufacturers can make them. Why? Simple: The picture quality is stunning.

Canon's XT is the much-improved replacement for the Digital Rebel EOS 300D. It's got a lighter body, faster focusing system and sharper resolution.

And Nikon tweaked the original D70 with new features, notably a larger preview screen. The newer, less expensive D50 is lighter than the D70 but larger than the Rebel XT.