Open Access

Open access (OA) refers to online research outputs that are free of all restrictions on access (e.g., access tolls) and free of many restrictions on use (e.g. certain copyright and license restrictions).[1] Open access can be applied to all forms of published research output, including peer-reviewed and non peer-reviewed academic journal articles, conference papers, theses,[2] book chapters,[1] and monographs.[3]

Read more...https://en.wikipedia.org/wiki/Open_access