Part of the Team Six Workshop, OER, Copyright and Licencing, looked at Creative Commons licences. Creative Commons is the infrastructure built to allow content creators legal controls over the copyright of the their work. More information about Creative Commons can be found on the Creative Commons site and the Lincoln Academic Commons site at http://commons.lincoln.ac.uk/creative-commons There are six different Creative Commons licences, each one giving the conditions under which the content can be shared, re-designed and re-licenced either commerically or non-commercially. Each licence can be identified with a relevant logo.
Attribution. CC BY. This licence means other people can use and reuse the OER, including commercially, as long as the original author is credited. This licence is recommended for ensuring content is most widely shared.
Attribution ShareAlike. CC BY SA. This license includes the same criteria as Attribution but anyone re-purposing it must license the new materials under identical terms.
Attribution-NoDerivs. CC BY ND. This license allows for commercial and non-commercial redistribution but it cannot be changed and the original author is credited.
Attribution-NonCommercial. CC BY-NC. This license is for non-commercial use. It allows others to re-use and re-purpose content. The original author must be cited but the new work does not have to be licenced under identical terms.
Attribution-NonCommercial-ShareAlike. CC BY-NC-SA. This license is for non-commercial use. It allows others to re-use and re-purpose content. The original author must be cited and the new work must be licenced under identical terms.
Attribution-NonCommercial-NoDerivs. CC BY-NC-ND. This is the most restrictive license. Work can be downloaded and shared, the original author must be credited but not changes can be made and the work must not be used commercially.
The Creative Commons site contains more information about background and development of these licence and also has a licence choosing tool designed to help you select the right licence for your own work.
Because the creator has the control over the copyright, sharing and distribution of their work, this is sometimes referred to copyleft.