[Orgmode] Newbie elisp programmer requests a pointer to backtics...

[Russell L. Carter]

Hi there,
Many thanks for org-mode and all of its amazing capabilities.  This elisp
newbie (but fluent in many other languages) has a concrete and simple request:

Where do I find good-enough documentation for the backtics
prefixing the parenthesis and the commas prefixing the associative
list values in the following code (lines of interest prefixed by
"here->", uninteresting lines elided):

(setq observer-base-dir "~/projects/blogs/observer")
(setq observer-blog-dir (concat observer-base-dir "/jekyll/_posts"))
(add-to-list 'org-publish-project-alist
here->         `("observer-blog"
here->         :base-directory ,observer-base-dir
here->         :publishing-directory ,observer-blog-dir
                .
                .
                .
here->            `("observer" :components ("observer-blog")))

I greatly prefer a pointer to the fundamental docs in lieu of an
explanation here.  I figured these out by mimicking working
code, and they work for me.  But what are these operators|delimiters
actually doing?

I have both the latest versions of the GNU Emacs Lisp Reference Manual
and the Introduction to Programming in Emacs Lisp, sitting before me
and they have been extensively interrogated, as has google.  Yet still
I have to bother the list.  I'm sorry!

Many thanks,
Russell