It's for people learning how to program for the very first time, to the point they need to be told to enter code into a text editor as opposed to, say, Microsoft Word. Or whatever Microsoft is calling its Word Processing Software Tool Universe For Non-Programmers this week.

(Yes, it might well be possible to coerce Microsoft Word into emitting plain text. The book does not assume its readers know that.)

From what I recall, the author is very opinionated in that he does things one way and expects readers to follow along exactly. The readership is at a level where this is a good thing: If you introduce options, people who know absolutely nothing get paralyzed by them, because they have no basis for making those kinds of decisions yet. It would be better if they flipped a coin, most likely, but most people seem reluctant to do that, because utter beginners are irrationally afraid of damaging things.

So the author has made all the decisions for them, and can get them to the point where they know enough to disagree.