SHERPA/RoMEO collects information about publisher policies related to online sharing (“archiving”) of works published in most journals. Journals and publishers are classified according to a color scheme that relate to the archive rights that authors retain. Authors are encouraged to research the policies of journals they have published in or are considering submitting a manuscript to in order to ascertain what rights in that work they will retain. Authors who wish to publish a copy of their articles will want to look for journals classified as green or blue, then check on any additional restrictions.
Publishers often make distinctions between three primary versions of a manuscript when detailing the archive or deposit rights retained by authors: the pre-print, the post-print and the publishers version.
Pre-print – A pre-print is the original version of the manuscript as it is submitted to a journal. While the authors may have sought help from their colleagues in selecting data analysis techniques, improving manuscript clarity, and correcting grammar, the pre-print has not been through a process of peer review. It typically looks like a term paper – a double spaced .doc file with minimal formatting.
Post-print – A post-print is a document that has been through the peer review process and incorporated reviewers comments. It is the final version of the paper before it is sent off the the journal for publication. It may be missing a final copyedit (if the journal still does that) and won’t be formatted to look like the journal. It still looks like the double spaced .doc file. Sometimes, the term “pre-print” is used interchangeably with “post-print,” but when it comes to permissions issues, it is important to clarify which version of a manuscript is being discussed.
Publishers version/PDF – This is the version of record that is published on the publishers website. It will look quite spiffy, having been professionally typeset by the publisher. Library databases will link to this version of the paper.
Generally speaking, publishers are more likely to be okay with authors posting copies of pre-print versus other manuscript versions. But each journal is different, and authors need to be aware of what they can do. The copyright transfer agreement is the best place to find this information.
From: http://blogs.scientificamerican.com/information-culture/2013/12/16/understanding-your-rights-pre-prints-post-prints-and-publisher-versions/
Author's Rights - General Resources
Author's Rights - Addenda for Publisher Contracts
The Creative Commons organization was founded in 2001 as a means of permitting creators to license their work for public use under conditions they specify. Although not an alternative to copyright and not an indication that a work is part of the public domain, Creative Commons licenses permit the holders of copyright to define more clearly, than perhaps modern copyright law interpretation allows, how their works may be used and give users of copyrighted works greater creative freedom when they know, without question, how copyrighted works can be incorporated into new creations.
From Technology Enhanced Learning Blog http://www.dontwasteyourtime.co.uk/elearning/creative-commons-infographic-licenses-explained/