Reference

Wikipedia

All the world’s knowledge

Wikipedia is a free, collaborative encyclopedia written in over 300 languages by volunteers around the world.

Wikibooks

E-book textbooks and annotated texts

Wikibooks aims to build a collection of free e-book resources including textbooks, annotated texts, instructional guides, and manuals.

Wiktionary

A dictionary for over 170 languages

Wiktionary is a free multilingual dictionary. The project aims to describe all words of all languages. It includes language resources such as a thesaurus, rhyme guide, and language statistics.

Wikiquote

Find quotes across your favorite books, movies, authors and more

Wikiquote is an online collection of sourced quotations from notable people and creative works in over 75 languages. It also includes proverbs, mnemonics and slogans.

Collections

Wikimedia Commons

114 million images, photographs, videos and music files and counting

Wikimedia Commons is the world’s largest free-to-use library of illustrations, photos, drawings, videos, and music.

Wikisource

The free library

Wikisource is a library of freely-licensed source texts and historical documents, including poetry, government documents, constitutions of many countries, and general literature.

Wikiversity

Access learning resources, projects and research at any level of study

Wikiversity is devoted to learning resources, learning projects, and research for use in all levels, types, and styles of education.

Wikispecies

The free species directory

Wikispecies is a species database for taxonomy that covers living and fossil representatives of Animalia, Plantae, Fungi, Bacteria, Archaea, Protista and all other forms of life.

Technology

Wikidata

The database of structured information collaboratively edited

Wikidata acts as central storage of structured data for Wikimedia projects. Structuring data into a machine-readable format makes it easier to view, search, edit, curate, use and re-use files.

Wikifunctions

The library of code functions anyone can edit

Wikifunctions allows everyone to collaboratively create and maintain code functions that can be used to answer questions, such as how many days have passed between two dates, or the distance between two cities.

MediaWiki

The software platform that makes Wikipedia possible

MediaWiki is free and open source wiki software that anyone can use and develop. It is the platform on which Wikimedia projects are built.

Guides

Wikivoyage

The ultimate travel guide

Wikivoyage aims to create the world’s largest free, complete and up-to-date worldwide travel guide.

Collaboration

Meta-Wiki

Project coordination software tool for global collaboration

Meta-Wiki is a project used as a central hub for various coordination and organization tasks, such as discussions affecting multiple wikis or planning upcoming events.

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