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. This far exceeds the highest data rate achievable through most networks. Until recently, the only practical ways to get video on a PC were to play video from a CD-ROM or to download a very large file across the network for playback at the user's desktop. Overcoming the Bandwidth Challenge It is obvious from looking at the available throughput.