Open access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions.
Green open access means publishing in a traditional journal and depositing a shareable version of the article in a subject or institutional repository. Most publishers allow the accepted manuscript copy to be shared in a subject or institutional repository like the Research Portal at Queen's.
Gold open access means that the published version of the research article is open access directly from the journal - the reader does not need to pay to read the article.
Open access is important because it enables researchers to share their work internationally and makes research easier to discover online.