A promo (a shorthand term for promotion) is a form of commercial advertising used in broadcast media, either television or radio, which promotes a program airing on a television or radio station/network to the viewing or listening audience.
Most promos comprise video or audio clips of scenes or segments from an upcoming program, such as a television or radio series, film or special.
Unlike with broadcast and cable television, airtime information is not pre-displayed on promos for syndicated programs, as syndicated programs are typically aired at different times depending on the market; they are instead inserted by the station itself).
An ad in the lower third of a TV screen during a show helps to remind people what network they are watching.
Some people have criticized the practice because it is distracting, and such ads may cover up subtitles and prevent information from being seen.