This document provides an overview of open access publishing. It defines open access as making peer-reviewed literature available to anyone free of charge. The benefits of open access publishing are discussed, such as increasing the reach of research. Various models of open access publishing are described, including gold open access where the final published version is openly available from the publisher, and green open access where an author archives their work in an open repository. Issues like predatory publishers, open access for books, and mandates from research funders are also covered.