General best practices:
It is important to read your publishing agreement to understand all terms that may impact ownership and use of your work. While terms can vary from publication to publication, here are some common terms found in agreements:
APCs shift the cost burden from the reader to the author.
APCs should not be confused with page charges long associated with both print and digital publications. Page charges are used to cover administrative costs as well as the cost of print publication, but do not make the article available in an open access (OA) model.
Read and Publish Agreements – A Read-and-Publish agreement is an agreement in which the publisher receives payment for reading and payment for publishing bundled into a single contract. This bundling together brings payment for publishing into a contractual arrangement rather than being addressed ad hoc by individual authors who are choosing open access publishing. In addition to publishing fees being brought under a contractual arrangement, a transformative agreement seeks to re-direct funds previously spent on subscription-based reading to the publishing component, often with a goal of a cost-neutral read-and-publish agreement in comparison with the previous subscription-based reading agreement.
Some information adapted from Ohio State University Libraries, Publishing your Research, CC BY as well as the excellent University of Alabama at Birmingham Open Access LibGuide
As defined and published in Nature:
Predatory journals and publishers are entities that prioritize self-interest at the expense of scholarship and are characterized by false or misleading information, deviation from best editorial and publication practices, a lack of transparency, and/or the use of aggressive and indiscriminate solicitation practices.
The following checklist can help you evaluate journals in which you are considering publishing. No check list is perfect or perfectly up-to-date. A legitimate journal to fail to meet one or more criteria, but a careful examination using these points as a departure can be useful.
Adapted from Cornell's Understanding and Avoiding Predatory Publishing
(red flags from The Predatory Paradox by Koerber, Starkey, Ardon-Dryer et al, licensed CC BY NC)