The Creative Commons organisation, founded in 2001, provides a tool allowing academics and others to share their work. A Creative Commons licence allows you to tailor your copyright to your exact needs, thereby offering readers and users a number of options with regard to copyright, eliminating the need for individual agreements for each case.
A Creative Commons licence also provides for open access to research findings or publications, without the author having to be too concerned with various legal aspects once such a licence has been attributed.
One example of use of a Creative Commons licence might be, for example, when an author wishes to give his institution licence to make a publication freely accessible via open access in an institutional archive, such as PURE. Here, the author can, for example, attribute a licence to a work called 'Attribution – Noncommercial – NoDerivatives (by-nc-nd), meaning that a work may be copied and made accessible to the public as long as sources are stated and it is not used commercially: http://creativecommons.org/licenses/by-nc-nd/3.0/
The least restrictive licence is 'Attribution' (by), which permits others to distribute your work and build on it, including change (remix) and adaption, even commercially, as long they credit you for the original work. This may be a relevant licence in the case of publication in a journal via a traditional publisher.
Creative Commons covers the area between full copyright – "all rights reserved" – and public domain, where all rights to the work are renounced, and it is sometimes referred to as "some rights reserved"
Creative Commons advises you to register your work at: http://www.creativecommons.org/choose/, thus allowing it, for example, to be retrieved via Creative Commons search machines.
Read more about Creative Commons on their website or at: http://wiki.creativecommons.org/Frequently_Asked_Questions