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Lists are Lisp's core data structure (LISP = LISt Processing). Create with list or '(...):

(list 1 2 3)              ; (1 2 3) — function call
'(1 2 3)                  ; (1 2 3) — quoted, no evaluation

The Big Three operators:

• (car list) — first element (head)
• (cdr list) — rest of list (tail)
• (cons x list) — prepend x to list

(car '(1 2 3))            ; 1
(cdr '(1 2 3))            ; (2 3)
(cons 0 '(1 2 3))         ; (0 1 2 3)

Alias: first = car, rest = cdr.

Higher-order list operations:

(mapcar #'(lambda (x) (* x 2)) '(1 2 3))   ; (2 4 6)
(remove-if-not #'evenp '(1 2 3 4 5))       ; (2 4)
(reduce #'+ '(1 2 3 4 5))                  ; 15
(reduce #'+ '(1 2 3 4 5) :initial-value 100) ; 115
(length '(a b c))                           ; 3
(reverse '(1 2 3))                          ; (3 2 1)