[LukeShu]

You are reading that right. If it makes it seem any more sane, that's because many text editors of the time weren't written for screens ("displays"), but for teletypes, where you couldn't possibly see your code verbatim as you were editing it.

https://en.wikipedia.org/wiki/File:ASR-33_at_CHM.agr.jpg

For example, the standard editor on early Unix was 'ed'. It is available on most modern *nix systems, if you care to try it :). Bill Joy later modified ed to be a display editor, or 'vi'sual editor; so if you have you have used Vi, it shouldn't be too unfamiliar.

[jemfinch]

vi evolved from ex (not ed), didn't it?

[LukeShu]

Well, ex is 'ex'tended ed, and vi and ex are the same program.

From 1976-1979, the way to open vi was to execute 'ex', and run the 'vi[sual]' command in ex. In 1979, ex learned to launch the 'vi' command automatically if argv[0] is "vi", and a symlink from 'bin/vi' to 'bin/ex' was added.