I'm a vim user, but I'm also an emacser too :) I will try to express
myself as clearly as I can.

vim has a feature for creating folding and use some other text instead
of header's for displaying, I attach a html to show it, from attachment,
you can see that vim can create a folding and use the infos extracted
from the folding body for displaying, I don't know how to do it in
emacs?

Another feature I miss is to generate html version of the plain text,
htmlize.el can do it, but see my attachment again, vim's 2htmlize even
can reserve the folding feature of the text, I don't know how to do it
in emacs too.