RE: C-d deleting region considered harmful

[Drew Adams]

> Likely.  Emacs has the cursor _between_ characters.  vi has the cursor
> _on_ characters.  So vi has commands for inserting before and after a
> character, before and after a line and so on.  Emacs has only one kind
> of insertion, _at_ point.

Yes.  Maybe this helps too:

The cursor is a graphic indication of the text insertion position, aka point.
The position is unambiguous, no matter how the cursor might indicate that
position.

Typically, when the cursor shape is not narrow enough to show between two chars
it is displayed more or less on top of the char that follows the insertion
point.

A bar cursor is narrow enough to show between two chars.  A box cursor is wide
enough that it is shown in Emacs on top of the char after point.