NTSC was devised in 1953. Besides transmitting this analog signal, it can be recorded on tapes such as VHS and Betacam. The NTSC standard is incompatible with most computer video standards, which generally use RGB video signals. However, you can insert special video adapters into your computer that convert NTSC signals into computer video signals and vice versa. Non-Interlaced means that one row of data after another is traced out.
Interlaced video means first the even rows are completely drawn and then the odd rows are drawn.
The odd or even set of rows are refered to as fields of the image. An advantage to Interlaced video is that you can start to see what the image will look like before it is completely drawn quicker than in a Non-Interlaced version. Number of Frames per second. The remaining lines are used for vertical blanking which is the return of the gun back to the top of the image. Some of these lines can be used to store cueing, testing and other information.