Broadcast

Broadcast is the transmission of audio, video, or data to a broad audience. Traditionally it refers to sending content over radio waves to many receivers from a single source, with the aim of reaching a mass audience rather than individuals. The term originates from farming, where seeds are scattered widely, implying widespread distribution.

Origins lie in early 20th-century radio experiments. The first public radio broadcasts occurred in the 1920s, leading to nationwide networks, with television emerging in the mid-20th century. From analog systems in the 20th century, broadcasting evolved to digital formats, enabling more channels and services, including multicasting and on-demand options.

Platforms and technologies: radio broadcasting uses amplitude (AM) and frequency modulation (FM). Television originally used analog signals and is now largely digital, delivered terrestrially, by satellite, via cable, or over the internet. Digital standards include DVB, ATSC, and ISDB. Broadcasting usually requires regulatory authorization and access to spectrum.

Types and economics: public service broadcasters aim to serve the public interest and may be funded by state, license fees, or public funds; commercial broadcasters rely on advertising and sponsorship; community broadcasters serve local communities. The rise of streaming and on-demand services has transformed audience habits and revenue models, with many traditional broadcasters offering online platforms.

Other uses: in computer networks, broadcasting also means sending a message to all devices on a network segment, contrasting with unicast or multicast.