Open Access (OA) is free, permanent, web-based access to scholarly publications. OA is the principle that research should be readily available immediately after publication and to anyone with access to the Internet. It is a movement, a business model, and is improving the way scholarly information is shared.
Gold: Gold OA refers to journals in which all articles and content are freely available to anyone with Internet access--without subscription fees--immediately upon publication. These journals are either funded by their organizations or by fees charged to the author or institution to cover publication expenses. Examples of Gold OA publishers include PLOS (Public Library of Science) and BioMed Central.
Green: Green OA occurs when the publisher of a subscription journal grants the author the ability to self-archive their work for free public access. Authors are able to provide access to pre- or post-print versions of their work (with publisher permission) in an institutional or disciplinary archive such as UF's Institutional Repository or arXiv.org.
Hybrid: Hybrid journals are subscription journals whose publishers offer authors the option of making their individual articles open access for a fee. This means that one or more articles in a hybrid OA journal may be freely available to anyone with Internet access while others are only available to those with a paid subscription.
Gratis: Gratis OA refers to information that is available free of charge, while traditional copyright and licensing restrictions may still apply.
Libre: Libre OA refers to information that is free of charge and free of most traditional copyright and licensing restriction.
OA publishing still often requires the author to pay a fee to publish their work. While some open access journals do not charge fees for publication to authors, others require payment of fees known as article processing charges (APCs) to subsidize publication costs.