# Lisp

Lisp (or LISP, an acronym for LISt Processing) is a family of interpreted programming languages. Lisp is one of the oldest family of programming languages still used, with modern variants including:

-   [[Clojure]]
-   [[Scheme]]

Lisp has a long and varied history.

Expressions in Lisp are called _[[s-expressions]]_, and they look like this:

```lisp
(+ 1 2 3)
```

where `+` above is a function, called with arguments `1`, `2`, and `3`.

Lisps are simple to implement due to their usage of s-expressions, as s-expressions are just [[ASTs]].