The open access (OA) movement has focused on the removal of barriers that stand between a user and information. Open access (OA) literature, data, and education resources are "digital, online, free of charge, and free of most copyright and licensing restrictions" (Peter Suber).
There are a number of contributing factors to the rise of the OA movement. The internet has introduced the possibility of broad dissemination, reach, and impact of research. It is a reaction to the fee-based model of scholarly publishing, in which access to scholarship is dependent on being affiliated with an institution that subscribes to journals and databases. Finally, funders, particularly those in the government sector, have established requirements that data and publications that result from research that they support be shared through an open access repository.
(Credit to original guide writer Nora Mattern.)
There are a number of reasons why open access is both important to the public good, beneficial to research, and expected by funders. Studies have suggested that open access publications will be more widely read and more frequently cited than those behind a pay wall (MacCallum and Parthasarathy, 2006). In addition to personal benefits for the author, making research more open is in the public interest, with individuals who are not associated with an institution with journal subscriptions able to access and build on an author's work.
There are a number of common myths surrounding open access that libraries and advocates have effectively debunked. Peter Suber's "A field guide to misunderstandings about open access" is a useful starting point for understanding the quality of OA publications, the funding model behind OA, and the relationship between copyright and OA.