RE: Dired question

> Is there some keybinding or command in Dired that  open in background
> all marked files (that is, put them in buffers, without actually
> displaying them in windows) ?

Load library dired-x.el, then, in Dired, mark the files, then use `F' with a
prefix arg: `C-u F'.

To find this out: Consult the Emacs manual, which mentions dired-x.el. Then in
Dired mode, do `C-h m' to get info about the mode.

Unfortunately, the doc string for `F' (via `C-h k F'), which is command
`dired-do-find-marked-files', says only this: "With optional NOSELECT just find
files but do not select them." What it neglects to mention is that the optional
argument NOSELECT corresponds to using a prefix argument (`C-u').

Put this in your init file to get dired-x.el: (require 'dired-x)
Or load it manually: `M-x load-library dired-x'.