Closed captions offer a text version of the audio in media files, enhancing accessibility for the deaf and hard of hearing by providing a synchronized text track that can supplement or replace audio. Beyond speech, they include non-speech elements like speaker IDs and sound effects, crucial for understanding the video’s full context. Typically, videos with closed captions are marked with a CC icon on the player.

Transcripts for multimedia content support accessibility by aiding users who are deaf, blind, or deaf-blind (through Braille devices), and those unable to access audio or video. They include descriptions of key audio and visual elements, improving searchability for users and search engines alike, and cater to screen reader users who prefer reading over listening. Providing transcripts ensures content is accessible and usable for a wide audience.

Audio descriptions are crucial for visually impaired users to access multimedia content, ensuring WCAG 2 Level AA compliance. Like Descriptive Video Service on TV, they narrate visual-only elements and can be integrated directly into videos, offered as separate audio tracks, or included in alternate video versions. While producing these descriptions requires resources, they are not needed if the existing audio already effectively conveys all visual information.