Scheme

Prefix notation

;;; Combination
(+ 5 64)

;;; Fundamental forms
define
lambda
set!

Print

(write-line "hello world")

Variables

(define pi 3.14159)

(define string "my string")

;;; Local state variables
(set! <name> <new-value>)

Data types

;;; List
(list 1 2 3 4)

Procedure

(define (square x) (* x x))

;;; Lambda
(lambda (x) (+ x 4))