I wasn't used to learning knowledge by watching videos or listening to podcasts before, and I also thought that classroom learning and online learning were very inefficient; only exploratory self-study could maintain extreme efficiency.

However, recently, while listening to some podcasts in a sports setting, I unexpectedly found that seemingly inefficient audio/video, with shorter scripts, had a different way of processing in the brain, leading to decent results.

Some good podcasts:

Silicon Valley 101

Zhang Xiaojun Business Interview

Half Latte