An improvement over the composite video was apparent by the introduction of component video. The component video takes different components of the video and breaks them into separate signals. This improvement led to various video formats, like S-Video, RGB, Y, Pb, Pr, etc. . . All of these analog formats however, susceptible to quality loss from one generation to the next when stored or reproduced. These limitations led to the birth of digital video.
Digital video is nothing more than a digital representation of the analog video signal.
Unlike analog video that degrades in quality from one generation to the next, digital video does not. Each generation of digital video is virtually identical to the parent. Digital video is generated by sampling and quantizing analog video signals. Until recently, digital video has been mostly stored on sequential tape because of the high capacity requirements, but advances in magnetic and optical disk capacity and speed make it economically feasible to store video on these media. Another challenge for digital video is that it requires extensive resources and transfer rate.