I was wondering that too. However it ended up having the best highlighting and indenting packages for the languages I was using. It was available on most platforms and most of all worked in an SSH session.

I wouldn't try to learn everything at once would just learn:

1) How to quit 2) How to save a file 3) Basic navigation: up, down, left, right, end of line, beginning of line 4) How to cut a line, and how to paste a line

Some of those you might already know from using bash or even basic text editing on macOS.