Background
Publish or Perish – you have certainly heard of this concept if you have been around academia for any length of time. In fact, most individuals working in an environment like ours include publishing in their long and short term career plans. 
Traditionally, an author submits a manuscript to a journal publisher along with an agreement to sign over copyright if accepted, and never considers the consequences of that particular signature. As a result, the publisher dictates the how the work can be used and by whom; the author, the institution (and its library) with which he/she is affiliated, along with the funding agency of the research, all have to abide by the limitations written into the agreement.
Public Access
Since 2008, scientists receiving funding from the National Institutes of Health (NIH) have had to negotiate with the publishers to allow a copy of the final edited manuscript to be deposited to PubMed Central within twelve months of publication, so that results of their publicly funded research is available to the public (i.e. taxpayers). The mandate for public access dictated by the funding agency is a legal requirement in the case of the NIH, but it can also come from private funders, e.g. the Wellcome Institute; non-compliance may limit future funding opportunities.
Open Access
As researchers/authors become more aware of the limitations and/or costs imposed on the use of their own hard work, the Open Access movement has evolved in recent years. They have come to realize that the majority of the effort that goes into a publication – grant-seeking, basic research, writing, editing, manuscript reviewing – comes from the academic community. Although publishers contribute to the process, and should be fairly compensated, they have created a system where authors have to give up practically all rights and privileges as content creators. The pressure to publish as a requirement for promotion and tenure within a defined timeframe gave authors little choice but to comply with the accepted model of “doing business”.
Open Access publishing is a continually evolving process, and provides many opportunities to both authors and scholarly communities that want to start new endeavors. New possibilities are also available because of today’s technological advances. There are numerous models in the marketplace, and each has its own advantages and pitfalls; however, one must be aware of enterprises where the process is downright unethical.