In broadcasting, the watershed is the time of day after which programming with content deemed suitable only for mature or adult audiences is permitted.
In the same way that a geological watershed divides two drainage basins, a broadcasting watershed serves as a dividing line in a schedule between family-oriented content, and content deemed suitable only for a more mature audience, such as programs containing objectionable content; this can include graphic violence, strong language, and sexual content, or strong references to those themes, even if they are not shown explicitly. The transition to more adult material must not be unduly abrupt and the strongest material should appear later in the evening.
In some countries, watersheds are enforced by broadcasting laws. Cultural differences around the world allow those watershed times to vary. For instance, in Australia, the watershed time is 19:30 (7:30 p.m.), and in Italy it is 22:30 (10:30 p.m.). In some countries, the schedule is divided into periods with progressively fewer restrictions. In addition, some countries are more lenient towards subscription television and radio or pay-per-view channels than towards free-to-air channels.
In Argentina, any programmes broadcast between 06:00 or 07:00 and 22:00 or 22:30 must be suitable for all ages. There are also three other ratings, SAM 13, SAM 16, and SAM 18, which may be broadcast only during the broadcast time that is not covered by any programme suitable for family viewing.
Starting in September 2010, it is compulsory for broadcasters to show the notices "Comienza el horario apto para todo público" (Start time of suitable for all age schedule) and "Finaliza el horario apto para todo público" (End time of suitable for all age schedule) at 6:00 a.m. or 7:00 a.m. and 10:00 p.m. or 10:30 p.m. respectively. In addition, the notice "Atención: Contenido no apto para niños, niñas y adolescentes" (Warning: Content not suitable for children and adolescents) are shown before news broadcasts.