"Why do people go to India to find themselves? India is where you go to LOSE yourself." ~ found on the Internet
I love watching movies on DVD with subtitles turned on as I can understand the dialogues better. Captions/Subtitles make videos and movies accessible to a wider audience. In India, PlanetRead reaches out to 300 million early literates by providing automatic reading practice using their Same Language Subtitling (SLS) technology on Bollywood songs shown on national television - Doordarshan. There are numerous other indirect advantages of Subtitling.
Last year, YouTube launched a Captions and Subtitles feature. YouTube currently supports a subtitle format that is compatible with the formats known as SubViewer (*.SUB) and SubRip (*.SRT). A SRT file (see sample) is a text file with captions and time at which it should appear in the video, written in a predefined format. YouTube Help Center has an entry on the list of free & commercial tools that can help you get these captions/subtitles files made for your videos. Uploading these generated caption files is then just a few easy steps. This process reminded me of how you can use a KML file to show custom locations on a Google Map or Live Map.
What's more YouTube can also Auto-Translate the subtitles. Although it may not be as effective as a human translation, it still helps. So if a song video has caption text, you can follow it better in the original language as well as in a language of your choice (for which translation is supported).
Also see: Sound Search Results