Closed captioning is the process of displaying text on a television, video screen or other visual display to provide additional or interpretive information to individuals who wish to access it. Closed captions typically show a transcription of the audio portion of a program as it occurs, either verbatim or in edited form. Occasionally closed captioning will including non-speech elements. A device or application is required to interpret and decode the embedded closed captions in order to display them on-screen and toggle on/off.
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