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Common Lisp was standardized in 1984 — the industrial-strength descendant of Lisp 1.5 (1962). Has features modern languages are still catching up to: full first-class macros, condition system, multiple inheritance via CLOS, optimizable type declarations.

A Lisp program is a list. The first element is the function, the rest are arguments:

(format t "Hello, Lisp!~%")

• format is the print function. t means stdout. ~% is newline.
• Parentheses define lists. Lists define calls.

Arithmetic uses prefix-style (everything is a function call):

(+ 1 2 3)        ; 6
(* 2 (+ 3 4))    ; 14
(- 10 3 2)       ; 5

Comments use ; for line, #| ... |# for block.

Unlike Clojure, Common Lisp is multi-paradigm and pragmatic — accepts mutation, uses dynamic typing, prefers clarity over purity.