It is also known as Y/C, it is an analog video signal that carries the video data as two separate signals, luma (luminance) and chroma (colour), unlike composite video which carries picture information as a single lower-quality signal, or component video which carries picture information as three separate higher-quality signals — typically luma and two chroma components.
S-Video, as most commonly implemented, carries 480i or 576i resolution video, i.e., standard definition video, but does not carry audio on the same cable.
The 4-pin mini-DIN connector (shown at right) is the most common of several S-Video connector types. Other S-Video connector variants include 7-pin locking "dub" connectors used on many professional S-VHS machines, and dual "Y" and "C" BNC connectors, often used for S-Video patch bays.
Early Y/C video monitors often used RCA connectors that were switchable between Y/C and composite video input. Though the connectors are different, the Y/C signals for all types are compatible.
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