Open access (OA) refers to free, unrestricted online access to research outputs such as journal articles and books. OA content is open to all, with no access fees.
There are two main routes to making research outputs openly accessible. One involves publishing articles or books via the OA route on a publisher’s platform (often referred to as gold open access). The other involves archiving a version of the manuscript in an OA repository (often described as green open access). Content published via the gold OA route is accessible immediately on publication, while manuscripts deposited via the green OA route may, in many cases, be made accessible only once a self-archiving embargo period has elapsed. The terms for onward sharing and re-use of OA content will depend on the licence under which it has been made available.