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+# Scheme
+Scheme is [Lisp](lisp.md) dialect created in 1975 by Guy Steele and Gerald Sussman at the MIT. Scheme is
+minimalistic and elegant leaning towards a functional programming paradigm, being the language used in the
+famous [SICP](sicp.md) book (using the MIT/GNU Scheme implementation).
+
+Scheme is standardized in a series of documents called *Revised Report on the Algorithmic Language Scheme* (RnRS) (where the `n` stands for
+the version), being the most popular revision the R5RS standard released in 1998.
+
+## Controversy around the R6RS revision (The Great Bloatening)
+In 2003 work in a new revision of Scheme began, R6RS, finished in 2007. This new revision was controversial since it
+added additional features that Scheme hackers deemed as a departure from Scheme's minimalism. In a attempt to amend this,
+work on R7RS began, splitting Scheme into two different (but still similar) languages, differing in the amount of features;
+a big language for "practical" use and a small minimalistic version.
+
+## Implementations
+Since Scheme (specially the R5RS standard) is simple, there are multiple implementations:
+- [CHICKEN Scheme](https://call-cc.org/): compiler (AOT) and interpreter.
+- [MIT/GNU Scheme](https://www.gnu.org/software/mit-scheme/): compiler, one of the "original" implementations, also includes a debugger.
+- [Chez Scheme](https://cisco.github.io/ChezScheme/): another classic compiler, freed in 2016.
+- ...
+
+## Examples
+### Hello World
+```scheme
+(display "Hello, Scheme!")
+```
+
+### Factorial
+```scheme
+(define (fact n acc)
+  (if (zero? n)
+	acc
+	(fact (- n 1) (* acc n))))
+
+(let ((ns '(4 0 5 10 1)))
+  (for-each (lambda (n)
+			  (display n)
+			  (display "! = ")
+              (display (fact n 1))
+              (newline))
+            ns))
+```