Academic outputs are available on an Open Access basis when they are freely available online to all users of the internet, and have clear re-use rights (allowing activities such as download for offline reading, text mining, and so on).
It's often difficult to read about Open Access without being confronted by jargon. Below is a quick guide to some of the terms that you're likely to come across.
GOLD OPEN ACCESS:
Gold Open Access outputs are those that are made available on an Open Access basis immediately upon first publication. This may or may not involve the payment of an "Article Processing Charge" (see below). With regards to journal articles, there are two main routes to making work available on a Gold Open Access basis:
The distinction between Fully Gold and Hybrid Gold Open Access is an important one that will influence where researchers submit their work. Researchers should only submit papers to a Fully Gold journal if they have guaranteed access to funds to pay the article processing charge, should their paper be accepted for publication.
GREEN OPEN ACCESS:
(also known as self-archiving)
Green Open Access outputs are those that are published in traditional, restricted access outlets, but then made available for free after an embargo period (determined by the publisher) in some form of online repository (see below). This is referred to as author self-archiving, as it is the authors of the papers who themselves deposit copies of their work in an online repository.
Deposit in the shared institutional repository, the Seals Digital Commons, ensures curation, long-term preservation and further dissemination of the scientific output of Rhodes University and access to this research for the conduct of internal and external evaluation. RU research publications include post-graduate theses and dissertations, peer-reviewed articles, book chapters, and conference papers and posters, and technical reports.
The nature of what can be self-archived varies between journals - usually only pre-prints or post-prints can be self-archived, though in some cases the publisher's own formatted version of the article can be self-archived (the SHERPA RoMEO database provides helpful guidance on individual journals' archiving policies).
DIAMOND OPEN ACCESS - "Free to read, Free to publish"
Diamond Open Access is an innovative Open Access model which addresses both cost and journal quality concerns as the Diamond model requires no article processing fees while maintaining journal quality. The emphasis of Diamond OA is on achieving academic goals: making knowledge production, dissemination and consumption as free as possible.
In Diamond Open Access, the author submits a preprint to a repository. What makes Diamond Open Access different from Green Open Access is that the preprint then becomes part of an "overlay journal" which is available online for free to readers and libraries. Because preprints are not peer reviewed, the overlay journal must have its own system of quality control or peer review. Some have an editorial review board funded by membership fees and donations while others use volunteer peer reviewers who do editing and reviewing without financial compensation.
PLATINUM OPEN ACCESS (no fees for readers and no article processing charges or publication fees for authors - Suber, Peter (November 2, 2006). "No-fee open-access journals". SPARC open access Newsletter.)
Platinum open access is a model of scholarly publishing that does not charge author fees. Platinum Open Access Journals are typically the ones run by professional associations and nonprofit organizations, and their economic model relies on membership dues and donations. Platinum Open Access journals run by government agencies are funded by tax.
BRONZE OPEN ACCESS (Used by Elsevier)
Journals that allow the self-archiving of papers usually do so after an embargo period. This embargo period runs from the first publication of your article in that journal. This means that during the period of the embargo you cannot make the full text of your article available freely online. The embargo period will depend on both the journal and on who funded your work; for example, journals may allow a shorter embargo period depending on who funded the initial research on which the article reports.
Rhodes University requires the full text of all publications to be made openly available upon deposit in the institutional repository or as soon as possible following deposit. In all cases, metadata should be openly accessible. For peer-reviewed publications, the deposited item can remain closed for up to 6 months (or for up to 12 months for publications in the social sciences and humanities). In the case of 'closed' publications, Rhodes University requires that the abstract of the deposited publication be made openly accessible with the aim of increasing its visibility.
For the avoidance of doubt, embargo periods will have no effect on how soon your article is made available on the publisher's own website.
More information on what version of your article you may be able to self-archive is given below in the sections on pre-prints and post-prints.
ARTICLE PROCESSING CHARGE:
This is the charge levied by some publishers of Gold Open Access publications to cover the costs associated with academic publishing i.e. copyediting, journal management, web hosting, and so on.
These are structured web-accessible databases containing academic outputs; sometimes pre-prints, sometimes post-prints. They are the principal means by which readers can access Green Open Access outputs, and their structured data ensures that their contents rank highly in search engine results.
An author's own version of an article before it has undergone peer review and traditional publication.
Please have a look at the two interviews below by Alina Helsloot (June 2019) to get a better understanding of the benefits of Pre-Prints for your research:
Lifting the lid on pre-prints: part one - More and more authors are using pre-print servers to get their research out quicker and to solicit feedback on their paper prior to sending ...
Lifting the lid on pre-prints: part two - As an academic author, what is important to know about pre-prints? We have asked two experts to shed some light on the topic
An author's own version of an article incorporating all the changes and suggestions required by peer reviewers and editors, but not the publisher's own copy-edited and formatted version. Many publishers allow the self-archiving of the post-print version of an article, but not the publisher's "official" formatted version. These are also often referred to as "Author's Accepted Manuscripts".