CMOS (Complementary metal-oxidesemiconductor) - definition
CMOS is one of two major types of image sensor technologies used in digital cameras (the other being CCD). The image sensor of a digital camera serves as a digital substitute for film in ordinary cameras.
The camera sensor captures light, converts it to electric charge and processes it into electronic signals.
Generally, CMOS sensors are smaller, cheaper and more energy efficient and currently deliver the same image quality as CCD sensors.