ATV Forum - A former membership association founded in 2000 that promoted interactive TV. It supported the Enhanced Content Specification originally developed by the Advanced Television Enhanced Forum (ATVEF). Regarding the SMPTE, the specification is known as Declarative Content Standard (DCS) and it provides an HTML and JavaScript delivery mechanism for adding content to interactive television programs. It also uses IP multicast over the vertical blanking interval for analog TV and data carousels for digital transmission. See ATVEF, Intercast and vertical blanking interval.