Self-archiving by authors is permitted under green OA. Independently from publication by a publisher, the author also posts the work to a website controlled by the author, the research institution that funded or hosted the work, or to an independent central open repository, where people can download the work without paying.Green OA is gratis for the author. Some publishers (less than 5 % and decreasing as of 2014) may charge a fee for an additional service such as a free license on the publisher-authored copyrightable portions of the printed version of an article.If the author posts the near-final version of their work after peer review by a journal, the archived version is called a "postprint". This can be the accepted manuscript as returned by the journal to the author after successful peer review. Journals
which publish open access
without charging authors article processing charges are sometimes referred to as diamond or platinum OA. Since they do not charge either readers or authors directly, such publishers often require funding from external sources such as academic institutions, learned societies, philanthropists or government grants The growth of unauthorized digital copying by large-scale copyright infringement has enabled free access to paywalled literature. In some ways this is a large-scale technical implementation of pre-existing practice, whereby those with access to paywalled literature would share copies with their contacts. However, the increased ease and scale from 2010 onwards have changed how many people treat subscription publications.
Relevant Topics in Medical Sciences