Broadcasting

Broadcasting is the distribution of audio, video, or data to a dispersed audience via radio waves, cables, or digital networks, typically to many recipients simultaneously. It contrasts with narrowcasting which targets specific individuals or groups.

Historically, broadcasting emerged from radio in the early 20th century, enabling simultaneous mass communication. Television followed, providing audiovisual content. The latter half of the 20th century saw satellite and cable distribution expand reach, while in the 21st century digital terrestrial, satellite, and IP-based broadcasting transformed delivery, including live streaming.

Types include radio broadcasting (AM/FM, digital radio), television broadcasting (analog and digital, DVB, ATSC, ISDB), cable and satellite distribution, and Internet-protocol based broadcasting and streaming. Some services combine broadcast and broadband, as in hybrid TV and over-the-top platforms.

Transmission and standards: broadcast signals are allocated spectrum by regulators; common modulation schemes include amplitude and frequency modulation for radio, and digital standards like DVB, ATSC, ISDB for TV, plus audio and video codecs. Networks rely on studios, distribution chains, and transmitter sites, with receivers in homes and mobile devices.

Regulation and economics: Public service broadcasters, licensing, content quotas, advertising revenue, and carriage agreements shape programming. Compliance with content and accessibility regulations, emergency alert systems, and copyright management are important aspects.

Contemporary context: Broadcasting now intersects with on-demand streaming and podcasting. It remains used for news, entertainment, and emergency communications, and continues to play a central role in cultural identity and information ecosystems.