ed is The Right Tool
https://portal.mozz.us/gopher/katolaz.net/0/ed_tutorial.txt (gopher://katolaz.net/0/ed_tutorial.txt)
«You know: ed is the standard text editor, and indeed you would find ed installed in any unix-like system. But I guess most Unix users have never actually tried to open it. The reason is probably that ed(1) is considered “hard-to-use” and “user-unfriendly”. I really see no reason for such misconceptions and no motivation for their popularity, so I will try to convince you with concrete examples and scientific evidence that ed is, almost always, The Right Tool to use.
This tutorial was originally publised as a series of “phlog” posts (a blog over gopher), in the hope to serve as an “ed-primer” for beginners. The eight posts are reported below in the same order as they appeared in the phlog. The only addition is the last paragraph of Section VII, which was not present in the initial series of phlogs. The references of each section are reported at the end of the section.
If you are in a rush and would like to go a proper book, look for the great “Ed Mastery” by Michael Lucas.»
— KatolaZ
Je vais peut-être traduire ce tuto en français. 🤔