The Open Access (OA) model supports the open dissemination of research and knowledge creation and refers to resources that are in digital format and available online and free of charge to the reader.
OA literature should undergo the usual scholarly publication processes, including peer review, copyright protection, and discoverability through indexing and other scholarly and research forums.
Two main models include:
Gold OA: scholarly works are published in an open access journal and available directly to the public for free through the publisher’s platform.
Green OA: publishers allow authors to self-archive a published or pre-publication version of their work, usually in a OA repository (organization or subject), for access to the public for free. Publishers may allow authors to archive immediately or after an agreed period. The journal will publish the final version using a traditional or an open access model.
Open Access journals - all articles are available for free to the public. Submitting authors may need to pay article processing charges.
Hybrid journals include both OA and subscription-based access to scholarly literature. Hybrid journals may charge article processing fees for publishing open access scholarly works and may allow authors to self-archive a version of a published paper.
OA repositories include institutional repositories, discipline, or format specific digital repositories. OA repositories do not support peer review processes, but may host articles already peer reviewed or may include some level of moderation for preprints. An author should own copyright or has received permission from the publisher to archive (for example, Green OA).