Definitely reading. Personally, videos are annoying, especially when big part of it is useless -- speaker introduction, "jokes" and other unrelated small talks.

Definitely reading. Personally, videos are annoying, especially when big part of it is useless -- speaker introduction, "jokes" and other unrelated small talks. Of course, the biggest shortcome is that you simply can't ctrl+f a specific keyword your are interested in and it takes much longer to find related info in a video. The only exception is social sciences, arts and humanities where context matters more and information I am looking for is broader than "what's the function name that does X".