On Sun, Dec 06, 2020 at 09:15:25PM +0100, daniela-spit@gmx.it wrote:
> 
> > Sent: Sunday, December 06, 2020 at 9:02 PM
> > From: tomas@tuxteam.de
> > To: help-gnu-emacs@gnu.org
> > Subject: Re: Using variables $ma in expression 'let'
> >
> > On Sun, Dec 06, 2020 at 08:57:22PM +0100, daniela-spit@gmx.it wrote:
> > > Notices that some code uses '$' in variable names.
> > >
> > > What is it about?
> > >
> > >    (let ((deactivate-mark nil) $ma $mb)
> >
> > Seen from Lisp's point of view, it's just a plain normal variable.
> >
> > But perhaps the code author wants to convey something to you,
> > the reader.
> 
> Thank you, I simply wondered if it was some special tag interpreted
> by emacs.
> 
> Do authors usually try to convey that a variable is only part of a function?

I think there's no general rule. Ask the author :-)

Cheers
 - t