SECAM, also written SÉCAM (sekam, Séquentiel de couleur à mémoire, French for color sequential with memory), is an analog color television system that was used in France, Russia and some other countries or territories of Europe and Africa. It was one of three major analog color television standards, the others being PAL and NTSC. Like PAL, a SECAM picture is also made up of 625 interlaced lines and is displayed at a rate of 25 frames per second (except SECAM-M). However, due to the way SECAM processes color information, it is not compatible with the German PAL video format standard. This page primarily discusses the SECAM colour encoding system. The articles on broadcast television systems and analog television further describe frame rates, , and audio modulation. SECAM video is composite video because the luminance (luma, monochrome image) and chrominance (chroma, color applied to the monochrome image) are transmitted together as one signal.
All the countries using SECAM are currently in the process of conversion, or have already converted to Digital Video Broadcasting (DVB), the new pan-European standard for digital television. SECAM remained a major standard into the 2000s.
Development of SECAM predates PAL, and began in 1956 by a team led by Henri de France working at Compagnie Française de Télévision (later bought by Thomson, now Technicolor). NTSC was considered undesirable in Europe because of its tint problem, requiring an additional control, which SECAM (and PAL) solved.
Some have argued that the primary motivation for the development of SECAM in France was to protect French television equipment manufacturers. However, incompatibility had started with the earlier unusual decision to adopt positive video modulation for 819-line French broadcast signals (only the UK's 405-line was similar; widely adopted 525- and 625-line systems used negative video). Nonetheless, SECAM was partly developed for reasons of national pride. Henri de France's personal charisma and ambition may have been a contributing factor.