There are two different sources of information about Emacs now:

1. Info manuals
2. Help documentation

They have different UI for the same purpose.

If the online Help documentation were in an Info manual,
that would have several advantages:

1. the same UI for browsing online documentation -
   Info manuals or Help documentation alike.

2. consistent cross references between Info manuals.

   For instance, a cross reference (info "(*Help*) Function car")
   will go to a virtual Info node equivalent to `C-h f car RET'.

   Previously visited cross references will be highlighted
   in a different face.

3. common history

   The `l' command will go back in the history to the last Info node
   with a function's docstring, etc.

4. other rich Info functionality will be available
   for the online Help documentation.

All this is easy to do using virtual Info manuals.

The patch below implements a virtual Info manual *Help*
with the following virtual nodes:

* Top - a menu of top nodes.

* About Emacs - like the About screen (`C-h C-a')
    displays the current version string and some useful links
    to other Emacs manuals.

* Statistics - the memory usage (garbage collection stats, etc.)

* Functions Index - a list of all defined functions

* Functions by Prefix
* Functions by Suffix - a list of functions grouped
    by common prefix/suffux

* Function <name> - like the output of `C-h f'
    with cross references to other Info nodes.

* Variables Index - a list of all defined variables

* Variables by Prefix
* Variables by Suffix - a list of variables grouped
    by common prefix/suffux

* Variable <name> - like the output of `C-h v'
    with cross references to other Info nodes.

* Buffers - a list of buffers

* Buffer <name> - complete information about buffer: name, major mode,
    cross references to nodes of its minor modes and buffer-local
    variables.

* Mule Diagnosis - a menu for all chapters of `describe-*' functions

** Input Methods

** Coding Systems

** Character Sets

...