#+title: s-expression
- tags :: [[file:20210307153455-programming.org][programming]] [[file:20210307152738-programming_languages.org][programming languages]]

An s-expression is a notation for listed data, often used by [[file:20200604222651-lisp.org][Lisp]] programming
languages, where they represent both the program and the data.

Initially s-expressions were just cons cells ([[file:20210307153829-linked_list.org][linked lists]]), so they could be
represented as:

#+begin_example
(1 . (2 . (3 . NIL)))
#+end_example

However modern Lisps either do not use linked lists or do not make this clear to
the programmer.