Okay, still working on #DataCamp, but the first thing I've learned is that I *really* do not benefit from watching videos as compared to reading books. I watch a video, then immediately go into the exercises needing notes in order to recall any part of what I just watched.

Since the data science functions being studied (in Julia-lang, R-lang, and Python + numpy + pandas) consist of dozens of similarly-named functions and methods, each with its own very different set of arguments, they're already hard to keep sorted in my head. The video method doesn't help with that.

Now, this may just be me. One of my friends ("S") says she doesn't read well enough to use books as her primary learning channel. But even she had to buy some books to help with her own video-based learning. There are reasons that in-person college / university learning programs also feature textbooks as a major part of their learning.