As digital technology has evolved so has the ability to disseminate information. Researchers now have more options for publishing their scholarly works, whether through traditional publishers (e.g. subscription journals) or open access (OA) publishers (e.g. free public access).
"Open Access is the free, immediate, online availability of research articles coupled with the rights to use these articles fully in the digital environment. Open Access ensures that anyone can access and use these results—to turn ideas into industries and breakthroughs into better lives."
Articles upon publication are freely and fully accessible in OA journals. Copyright is retained by the author(s) and most of the permission barriers are removed; however, costs are often still associated with publishing in OA journals through article processing charges (APCs), which can be paid for by the author, an institution, or sponsor.
Refers to the self-archiving of a or article in an online repository. Repositories can be disciplinary-specific (e.g. arXiv, PubMed Central) or institutional types hosted by an organization or university (e.g. Scholarly Commons). Whereas gold OA models can be costly, the benefit for green OA is the avoidance of costs; however, the challenges associated with green OA often involve the ability for authors to retain the necessary copyright permission to share their work.
Allows for articles upon acceptance in a traditional subscription journal to be made available OA if the author pays a fee. Although many publishers refer to hybrid journals as gold OA journals, hybrid journals are still primarily subscription journals with an OA option for individual articles.