Rosetta Code is a wiki

Wiki

A wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...

-based programming chrestomathy

Chrestomathy

Chrestomathy is a collection of choice literary passages, used especially as an aid in learning a foreign language.In philology or in the study of literature, it is a type of reader or anthology which presents a sequence of example texts, selected to demonstrate the development of language or...

 website with solutions to various programming problems in many different programming languages. It was created in 2007 by Mike Mol. Rosetta Code includes 450 programming tasks, and covers 351 programming languages. The site's content is licensed under the GNU Free Documentation License

GNU Free Documentation License

The GNU Free Documentation License is a copyleft license for free documentation, designed by the Free Software Foundation for the GNU Project. It is similar to the GNU General Public License, giving readers the rights to copy, redistribute, and modify a work and requires all copies and...

 1.2, though some components may be dual-licensed under more permissive terms.

Data and structure

The site is organized as a browseable cross-section of tasks (specific programming problems or considerations) and programming languages. A task's page displays visitor-contributed solutions in various languages, allowing a viewer to compare each language's approach to the task's stated problem. Task pages are included in per-language listings based on the languages of provided solutions; a task with a solution in C

C (programming language)

C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....

 will show up in the listing for C. If the same task has a solution in Ruby

Ruby (programming language)

Ruby is a dynamic, reflective, general-purpose object-oriented programming language that combines syntax inspired by Perl with Smalltalk-like features. Ruby originated in Japan during the mid-1990s and was first developed and designed by Yukihiro "Matz" Matsumoto...

, the task will appear in Ruby's listing as well.

Selection of languages

The following represents a sample of the languages found on Rosetta Code, ordered by sitewide application:

1. Tcl
   Tcl
   Tcl is a scripting language created by John Ousterhout. Originally "born out of frustration", according to the author, with programmers devising their own languages intended to be embedded into applications, Tcl gained acceptance on its own...
   
   
2. Picolisp
   Picolisp
   PicoLisp is an open source Lisp dialect. Itruns on Linux and other POSIX-compliant systems.- Features :Its most prominent feature is "simplicity". It is built on top of a singleinternal data type , without giving up flexibility and expressivepower...
   
   
3. Python
   Python (programming language)
   Python is a general-purpose, high-level programming language whose design philosophy emphasizes code readability. Python claims to "[combine] remarkable power with very clear syntax", and its standard library is large and comprehensive...
   
   
4. J
   J (programming language)
   The J programming language, developed in the early 1990s by Kenneth E. Iverson and Roger Hui, is a synthesis of APL and the FP and FL function-level languages created by John Backus....
   
   
5. C
   C (programming language)
   C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
   
   
6. Ada
   Ada (programming language)
   Ada is a structured, statically typed, imperative, wide-spectrum, and object-oriented high-level computer programming language, extended from Pascal and other languages...
   
   
7. Ruby
   Ruby (programming language)
   Ruby is a dynamic, reflective, general-purpose object-oriented programming language that combines syntax inspired by Perl with Smalltalk-like features. Ruby originated in Japan during the mid-1990s and was first developed and designed by Yukihiro "Matz" Matsumoto...
   
   
8. Go
   Go (programming language)
   Go is a compiled, garbage-collected, concurrent programming language developed by Google Inc.The initial design of Go was started in September 2007 by Robert Griesemer, Rob Pike, and Ken Thompson. Go was officially announced in November 2009. In May 2010, Rob Pike publicly stated that Go was being...
   
   
9. PureBasic
   PureBasic
   PureBasic is a commercially distributed procedural computer programming language and integrated development environment based on BASIC and developed by Fantaisie Software for Windows 32/64-bit, Linux 32/64-bit, and Mac OS X. An Amiga version is available, although it has been discontinued and...
   
   
10. Perl
    Perl
    Perl is a high-level, general-purpose, interpreted, dynamic programming language. Perl was originally developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions and become widely popular...
    
    

Selection of tasks

The following represents a sample of the tasks found on Rosetta Code, ordered by sitewide involvement.

1. Hello world/Text
   Hello world program
   A "Hello world" program is a computer program that outputs "Hello world" on a display device. Because it is typically one of the simplest programs possible in most programming languages, it is by tradition often used to illustrate to beginners the most basic syntax of a programming language, or to...
   
   
2. 99 Bottles of Beer
   99 Bottles of Beer
   "99 Bottles of Beer" is a traditional song in the United States and Canada. It is popular to sing on long trips, as it has a very repetitive format which is easy to memorize, and can take a long time to sing. In particular the song is frequently sung by children on long bus trips, such as class...
   
   
3. Comments
   Comment (computer programming)
   In computer programming, a comment is a programming language construct used to embed programmer-readable annotations in the source code of a computer program. Those annotations are potentially significant to programmers but typically ignorable to compilers and interpreters. Comments are usually...
   
   
4. Empty program
5. 100 doors
6. Fibonacci sequence
   Fibonacci number
   In mathematics, the Fibonacci numbers are the numbers in the following integer sequence:0,\;1,\;1,\;2,\;3,\;5,\;8,\;13,\;21,\;34,\;55,\;89,\;144,\; \ldots\; ....
   
   
7. Function definition
   Subroutine
   In computer science, a subroutine is a portion of code within a larger program that performs a specific task and is relatively independent of the remaining code....
   
   
8. FizzBuzz
9. Ackermann function
   Ackermann function
   In computability theory, the Ackermann function, named after Wilhelm Ackermann, is one of the simplest and earliest-discovered examples of a total computable function that is not primitive recursive...
   
   
10. Factorial
    Factorial
    In mathematics, the factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal to n...