Closed captioning and subtitles has been part of accessible media since 1972 and has played a large role in the development of disability rights as well as civil rights in the United States. Created initially for the Deaf and hard-of-hearing, it has been implemented on a large scale since that time across television programming via video captioning and now on the Internet with YouTube closed captioning. The primary benefit of closed captioning services is to provide a convenient visual interpretation through text or symbol of televised audio content including speech, music and sound effects.

The first demonstration of closed captioning was at the First National Conference on Television for the Hearing Impaired in 1971. By 1976, PBS was a major proponent in engineering and transmitting the technology of closed captions to television viewers for pre-recorded programs.

Real-time captioning of live broadcasts was developed by the National Captioning Institute in 1982. This process involved the use of highly trained individuals capable of typing over two hundred words a minute to produce captions in close to real time. Public television station WGBH-TV in Boston, one of the earliest users of closed captioning, remains a major producer of captions.

In 1980, through the influence of the newly created National Captioning Institute, commercial television stations began regularly scheduled uses of closed captioning through a telecaption adapter. Large steps have been taken in the last 30 years to make closed captioning more readily accessible to the Deaf and hard-of-hearing. The technology is now programmed directly into televisions themselves, making adapters obsolete. In 2014, the FCC approved implementing higher quality standards for text-based interface, ensuring that progress in these technologies continues.

In the development and increased use of subtitles over the past 42 years, there have been many innovations, including the translation and transcription of audio content in a variety of languages. These translations have become common in the modern film and television industry. Closed captioning in the United States is now required to be available for regular Spanish-language television programming.