Here’s the intro:
Though relatively few websites are required to provide closed captions for their videos, any website with significant video content should consider captioning. Not only does it provide access for deaf and hard-of-hearing viewers, but captions and the associated metadata can dramatically improve video search engine optimization. In this introduction to closed captions, you’ll learn about who needs to caption and who doesn’t (and why you may want to anyway), the available workflows for captioning live events and on-demand files, and a bit about web caption formats and how to marry them to your streaming files.
If you’re interested in captioning, the article should provide a good intro. Click here to view the article.