Audio narration of video media or animated graphical content provides an accessible alternative for blind students. It consists of an audio track of a narrator describing the action in the video or animation, often during natural pauses in the audio, and sometimes during dialog (if necessary). In some media players, audio narration can consist of a separate audio track to the video which includes descriptive text. When using players that don't support multiple audio tracks, the audio content can be included as a separate audio file. It is also helpful to provide a textual version of the narration that is screen-reader accessible, which may also be useful to students with hearing impairments (in addition to captioning of the video).
For more information on creating descriptive narration, please see Description Key. There is also a handy tip sheet on creating descriptive audio. Finally, see Providing Video for some examples of making video content accessible for programming labs.