Quote
This is quote. There is no computing. Just return itself.
'(list a b)
=>(list a b)
Backquote + Comma
This is a backquote to return itself,
but you can use ,
to computing inside.
`(list ,(car (list 'a 'b)) b)
=>(list a b)
Comma + At
The expression will be expanded in place. Useful for dynamic arguments.
(setq a (list a b))
`(list ,@a)
=>(list a b)