Copyleft
![](/w/images/thumb/8/8b/Copyleft.svg/200px-Copyleft.svg.png)
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.