Questions about parser state

[Xue Fuqiao <xfq.free@gmail.com>]

Hi,

I have two questions about parser state in Emacs Lisp.  In (info
"(elisp) Parser State"):

   Here are the meanings of the elements of the parser state:
[...]
  5. ‘t’ if the end point is just after a quote character.
[...]
  7. What kind of comment is active: ‘nil’ if not in a comment or in a
     comment of style ‘a’;

My question is:
1. What does the "quote character" mean?  Does it mean "'" in Lisp?  If
   so, what about "," and "#"?
2. What is comment style ‘a’?  In (info "(elisp) Syntax Flags"): "A
   comment style is a set of flags ‘b’, ‘c’, and ‘n’, so there can be up
   to 8 different comment styles."  I can't find an ‘a’ style.

I've also searched the archives/web, but didn't get anything that looked
promising.  Can anyone point me in the right direction?

-- 
Best regards, Xue Fuqiao.
http://www.gnu.org/software/emacs/