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Many video terms are Greek to IT professionals, unless the terms are also used in stereo instructions. Luckily, video is transmitted for the most part in only three standards: NTSC (National Television Standards Committee), which operates at 29.97 frames per second, is used in the United States, Japan and most other countries; PAL (phase alternation by line) operates at 25 fps and is used in the United Kingdom. France and some other countries use SECAM (Sequential Couleur Avec Mémoire, or Sequential Color With Memory). Although SECAM is similar to PAL in several ways (such as the 25-fps frame rate), the two standards are not compatible.

Video signals can be broken down into two main categories: composite and component. Most people are familiar with composite video, which is the standard connection for cable TV and most consumer VCRs. Composite video encodes the color and black and white pixel information into one analog stream. This produces a lower-quality video signal because there is not enough separate information to fully describe the pixels being rendered -- only an approximation is described.

Component video comes in several different flavors, depending on how the signal is broken out. Component breaks the video signal into separate pieces. Currently, the most common form of component video is S-Video, or Y/C. Introduced as a step up from composite, S-Video separates the signal into black and white information (Y) and color information (C).

True component video breaks the signal down even further -- into separate red, green and blue (RGB) signals. Most computer monitors today use component video, though it's not employed in the video world. For component video to stay compatible with older black and white television sets, a luminance signal is required. Because of transmission requirements, however, the bandwidth has not been available to broadcast separate RGB and luminance data. Luminance is the brightness of an image -- how black or how white the image is. Because the human eye sees better detail in green colors than in reds or blues, green is used as the luminance signal, thereby giving a clean signal that will work for both black and white and color televisions. This type of signal is referred to as YUV or YIV: The luminance is contained in the Y, and two signals describe the color of the signal (UV).