backquote quote pair notation: What does it mean in Emacs document?

[ziqianggeoffreychen]

Hi all,

When I read Emacs documents, I often see this kind of notation:

`'

For example, `q' in the following sentence:

setq does not evaluate symbol; it sets the symbol that you write. We say that 
this argument is automatically quoted. The `q' in setq stands for "quoted." 
(source: http://www.delorie.com/gnu/docs/elisp-manual-21/elisp_146.html)

One more example, `#level' in the following sentence:

Emacs detects such recursion and prints `#level' instead of recursively 
printing an object already being printed. (source: 
http://www.delorie.com/gnu/docs/elisp-manual-21/elisp_267.html)

Anybody knows the philosophy? Thank you for your reply.

Best regards,
Geoffrey Chen