How many times have I seen a $200 or $300 camera advertised with 20x zoom. Wow, would be the first response of a naive reader. Let the buyer beware is my advice. Most low end digital cameras advertise the total zoom range of their camera. This involved two different types of zooms: optical and digital. Optical zooms are desirable. They magnify the image without a loss of image quality. Their only drawbacks are their size and that they require more light than a non zoomed image. By requiring more light, you shutter time will increase. Therefore, depending upon your exact photograph it may be a hinderance.
See the following images that demonstrate an optical and digital zoom. Notice that there is no degration in image quality on the optical, but in the digital image the loss of sharpness is readily apparent.
Never use a digital zoom. It is always best to magnify the image once its been loaded into the computer as opposed to it having your camera perform the operation. Think about it, which is more likely to produce a better job processing your image, a small camera or the full resources of your desktop/laptop computer?