Broadcasting is the distribution of audio and/or video signals which transmit programs to an audience. The audience may be the general public or a relatively large sub-audience, such as children or young adults.

The sequencing of content in a broadcast is called a schedule. As with all technological endeavours, a number of technical terms and slang have developed. A list of these terms can be found at list of broadcasting terms. Television and radio programs are distributed through radio broadcasting or cable, often both simultaneously. By coding signals and having decoding equipment in homes, the latter also enables subscription-based channels and pay-per-view services.

The term "broadcast" originally referred to the sowing of seeds by scattering them over a wide field. It was adopted by early radio engineers from the Midwestern United States to refer to the analogous dissemination of radio signals. Broadcasting forms a very large segment of the mass media. Broadcasting to a very narrow range of audience is called narrowcasting.