Enable Closed Captions

When a user watches a video-lesson from any YouTube video that is originally closed captioned, a CC button will appear to enable/disable the subtitles:

There might be videos subtitled in different languages. To be able to go through all of them please click the `CC` button again. 

Please note that some videos may seem closed captioned from YouTube, but most of them use a speech recognition technology to automatically generate closed captions on the fly, which unfortunately doesn't work on other sites - like ours.