LISP is very expressive when it comes to documentation

Program Comment

;;;; Describe Program
 

Stand-Alone Line Comment

(atom 2.22)
;;; Comment that takes its own line
(atom 2.23)

Indented Comment

(defun hello-world ()
  ;; My indented comment
  (print "hello world!"))

After-Line Comment

(atom 2.15) ; my after-line comment

Multiline Comment

#!!
Multiline
comment
!!#