Zoom refers to the ability of the camera to stay constantly focused while the target image is made to appear closer or further away. There are two types of zoom: optical and digital.
Optical Zoom
Optical zoom is performed by the lens itself-either automatically or with a manual control. When buying a digital camcorder, pay close attention to the optical zoom ratios. Ratios of 12:1 (12x) to 25:1 (25x) are quite common-with the 25x being the best, and most expensive, of the bunch. If cost is an issue, a good balance of cost and quality can be found in the 16x range. If you decide to throw caution to the wind and invest in the best zoom possible, you'll want to buy a camera that can accept optional lenses.
Digital Zoom
When it comes to digital zoom, ignore the hype. Some camcorder manufacturers proudly boast of 300x, 500x, or even 750x digital zoom capabilities. Unfortunately, with digital zoom, the image is electronically manipulated, and image quality is significantly degraded at large digital zoom ratio. The most you'll ever actually need for digital zoom (if you want to maintain the resolution quality), is double-maybe triple-the optical zoom ratio (eg, if your optical zoom is 20x, your digital zoom doesn't really need to be more than 40x or 60x).
