articles/lisp.md: new article

articles/lisp.md

@@ -0,0 +1,27 @@
+# Lisp
+Lisp (originally LISP for **Lis**t **P**rocessing) is a family of [programming languages](programming_language.md) that share common features
+such as the S-Expression syntax, powerful metaprogramming capabilities with macros adding extensibility, the use of lists
+as the principal data structure, first-class functions (lambdas), garbage collection and recursion.
+
+Lisp was created in 1958 by John McCarthy, making Lisp on of the oldest languages used today, second to Fortran.
+Originally Lisp didn't use the now ubiquitous S-Expression syntax but M-Expressions (as used in the Lisp 1.5 manual), however S-Expressions turned
+out to be more popular and Lisps began using it.
+
+Unlike other languages at the time and also modern languages, Lisp is homoiconic, that is, Lisp source code is data that can be manipulated
+by the program itself. This gives Lisp powerful metaprogramming capabilities through the use of macros which modify the program data at compile
+time. Therefore, Lisp source code directly represents the program as a tree without extra superfluous syntax (as in "mainstream" programming languages).
+
+A PDF of the original Lisp 1.5 manual can be found here: <https://www.lispmachine.net/books/LISP_1.5_Programmers_Manual.pdf>. Head to page 13 for
+enlightenment.
+
+## Lisp languages in use
+- Scheme: created by the hackers Guy Steele and Gerald Sussman in 1970 at the MIT. Has multiple implementations, Chez Scheme,
+Chicken Scheme, MIT/GNU Scheme, etc.
+- Common Lisp: Big for Lisp standards (still better and smaller than "modern" languages), is also the most used Lisp today.
+The main implementation is sbcl, a public domain JIT compiler.
+- GNU Guille
+- Clojure: based in the [JVM](jvm.md) (Java Virtual Machine), does not have `cons`, `car` or `cdr`.
+- ...
+
+## Examples
+TODO