@Jayster I also had a similar feeling. Mainly I struggled with reading their syntax. It is great how detailed they are but sometimes I just want a bare bones way that just gives the gist of a method.
What I ended up doing and found helpful was as I go along I write down each method used into a personal desktop wiki. I rewrite a method in a way that makes it easier for my brain. So str.charCodeAt(index) become var utfCodeNum = str.charCodeAt(indexPos);