Copyleft

Copyleft symbol used under copyleft. Click on file description for attribution page that is mirrored from the Wikimedia Commons

Copyleft is a licensing style where much of that which is or can be protected under copyright is given to the users, hence the term in Finnish is fi."käyttäjänoikeus" == en."user's right".

It was first popular in free software but has since expanded to include various other types of works of art or utility, most known of which is of course the Wikipedia.