One of the most significant differences between Open and Closed Access publishing is the way in which the publishing is funded. In traditional Closed Access publishing, payment is expected from the end user through either an individual or institutional subscription. Open Access publishing does not require payment from the reader and therefore must fund the work differently. This can be done through support from professional organizations, consortiums, volunteer work, or article processing or publishing charges (APCs). Some closed-access journals are beginning to offer a hybrid model where an author can pay an APC in order to make their article available for free.
Infographic from Jill Cirasella and Les Larue
What's the Problem? Universities, funded by taxpayer money and/or tuition, often also receive grants. These institutions pay faculty to research and report on results in articles. Faculty then give the results of their articles and copyright to publishers for free to be peer-reviewed by other faculty while publishers rake in the money based on the labor they are not paying for. Elsevier's profit margin exceeded Google's, and many students, researchers and others still can't get the articles they need and libraries cannot afford many journals.