The appearance and disappearance of the odd and even picture fields causes noticeable flickering of thin, horizontal lines, such as those in spreadsheets. The computer signal, by contrast, was designed specifically for displaying non-moving, detailed images such as small text and spreadsheets. This is accomplished with a non-interlaced signal, also called progressive scanning. In progressive scanning, the horizontal lines on a computer screen are painted progressively, left to right, top to bottom, in a single pass. Therefore, the flickering problem encountered in interlaced TV video does not exist in computer video.
Composite video is the most commonly used format.
Remember, while all of these formats differ in the way the video information is combined into a signal, they still have certain things in common. Unlike TV video, there is no single standard by which all computer video signals must abide. As discussed earlier, there is a wide range of commonly used display resolutions. There is an equally wide range of refresh rates, most falling between 60 and 85 Hz. And, while almost all computer displays are non-interlaced, some video display cards do offer an interlaced display option.