Systeme Electronique Couleur Avec Memoire (SECAM) is a television signal standard (625 lines, 25 frames per second) that uses an FM color subcarrier that carries the color difference signals somewhat similar to PAL.
Instead of all the color difference information being transmitted all at once, in SECAM the color difference signals are transmitted sequentially: R-Y on one line and B-Y on the next. A delay line in the receiver provides the necessary time delay for making R-Y and B-Y available for display at the same time and thus the term "Memoire" as part of the standard's name.
SECAM was developed in France and is used in France and it's territories, much of Eastern Europe, Russia, the Middle East and northern Africa.
