Open access (OA) scholarship is available online and can be read for free. It is often available for use and sharing without copyright and licensing restrictions commonly placed on published works. By making their work available in this manner, authors ensure that the broadest possible audience can read and use it, without limiting it to only those who are affiliated with research libraries or who can afford costly journal subscriptions.
Open access is not defined by a particular business model or type of content. Rather, open access is an approach to sharing one's work with the wider world. To learn more about open access, consult the resources below.
Open Access by Peter Suber
A free e-book (available in a variety of formats) covering the basics of open access, including definitions, history, business models, funding, and much more.
"Open Access," Wikipedia
A comprehensive overview of what open access is, how it is implemented, and suggestions for further reading.