Simplified Common Lisp reference
quote
Symbol class: Functions, Evaluation, Flow Control, Definitions and Syntax
Syntax:
Symbol type: special form
quotedata => value
Argument description:
data data

QUOTE is special form for data quotation. The apostrophe character is reader macro synonym for QUOTE. See also FUNCTION.

(+ 1 2 3) => 6
(quote (+ 1 2 3)) => (+ 1 2 3)
'(+ 1 2 3) => (+ 1 2 3)
(let ((some-symbol 4)) some-symbol) => 4
(let ((some-symbol 4)) (quote some-symbol)) => SOME-SYMBOL
(let ((some-symbol 4)) 'some-symbol) => SOME-SYMBOL
Function indexFull documentation for quote (HyperSpec)