Files from Wikimedia Commons can be used across all Wikimedia projects in all languages, including Wikipedia, Wiktionary, Wikibooks, Wikivoyage, Wikispecies, Wikisource, and Wikinews, or downloaded for offsite use. As of May 2020, the repository contains over 61 million free media files, managed and editable by registered volunteers.
The project was proposed by Erik Möller in March 2004 and launched on September 7, 2004. A key motivation behind the setup of a central repository was the desire to reduce duplication of effort across the Wikimedia projects and languages, as the same file had to be uploaded to many different wikis separately before Commons was created.
The aim of Wikimedia Commons is to provide a media file repository "that makes available public domain and freely-licensed educational media content to all, and that acts as a common repository for the various projects of the Wikimedia Foundation." The expression "educational" is to be understood according to its broad meaning of "providing knowledge; instructional or informative".
Educational and professional opportunities: Commons helps improve european key competence such as: 4 Digital competence; 5 Personal, social and learning to learn competence; 6 Citizenship competence; 7 Entrepreneurship competence; 8 Cultural awareness and expression competence.
Read more details about pedagogical opportunities of open education.