Scholarly Publishing and Academic Resources Coalition (SPARC) defines Open Access (OA) as "the free, immediate, online availability of research articles coupled with the rights to use these articles fully in the digital environment." This is done through both the publishing and archiving of scholarly publications.
Open Access Publishing refers to the ways in which an author provides their research for publication, including any fees (called Article Processing Charges, or APCs) paid to the publisher and rights retained or waived by the author.
Green – Authors are allowed self-archiving, generally of the pre- or post-print of articles in an institutional repository.
Open Access Archiving refers to the ways in which a publication is made available to others and the rights of the author and publisher for sharing the published work.
Aimed at UK researchers, there is information that can be valuable to researchers everywhere regarding journals with open access publishing models.