I know markup languages and have experience editing python and c++.
There are at least half a dozen ways of creating a class; all acceptable. As C++ hides its soft pointer underbelly as much as possible, JS hides its prototype foundation. Stick with modern
class syntax; it’s generally less quirky than other methods. At the same time, you have to know that others exist. The
this can be an odd moving target.
I suppose, as with the
class thing, you want to be aware of when a tutorial was written. The language has grown of the years.
You can play around with JS sans browser with something like node: good for just quickly testing things out.