My mic to the world...
Image-sensor chips -- the chips that capture the image in digital cameras -- fall into two main camps: CCD, or charge-coupled device, and CMOS (pronounced see-moss), which stands for complementary metal-oxide semi-conductor. The main argument in favor of CCD chips is that they're more sensitive than CMOS chips, so you can get better images in dim lighting. CCD chips also tend to deliver cleaner images than CMOS chips, which sometimes have a problem with noise -- small defects in the image. On the other hand, CMOS chips are less expensive to manufacture, and that cost savings translates into lower camera prices. In addition, CMOS chips are less power-hungry than CCD chips, so you can shoot for longer periods of time before replacing the camera's batteries. CMOS chips also perform better than CCD chips when capturing highlights, such as the sparkle of jewelry or the glint of sunlight reflecting across a lake. CCD chips suffer from blooming, which means creating unwanted halos around very bright highlights, while CMOS sensors do not. Currently, an overwhelming number of cameras use CCD technology. But cameras manufacturers are working to refine CMOS technology, and when they do, you can expect to hear more about this type of camera.