Green vs. Gold
UNBC’s colours? Yes, but also two types of OA publishing. These are the two main ways that researchers make their work accessible.
In traditional publishing, readers pay to access articles. In Gold Open Access, the costs of publishing are shifted from the user to the producers. Some journals charge authors fees to have work made freely available to users worldwide while others are subsidized through institutions or advertisement. Well-known examples include PLOS One and BioMed Central.
In Green Open Access, articles may be published in traditional journals, but authors also place copies in institutional or subject repositories so their research is still accessible to everyone. This is often referred to as self-archiving. Examples of subject repositories are arXiv.org in Physics and PubMed Central in Biomedical and Life Sciences. See the Open Access Resources page for more subject repositories.
Free Food vs. Free Speech
There can also be some big differences between what the reader can do with the materials accessed. Sometimes, OA may be called either libre or gratis. It’s important to remember that green/gold and libre/gratis can be mixed and matched.
Gratis OA is sometimes compared to “free food” in that it’s OA that allows a reader to access the material at no cost. Just like free food, gratis OA can be consumed–you can read as much as you’d like as many times as you’d like. However, it’s not possible to do much else.
Libre OA is free as in “free speech,” meaning that there are almost no restrictions on how it can be used. Libre OA means that not only can you access the work, but you can also share it, modify it, and re-use it how you see fit. Usually, the only restriction on libre OA is attribution–the original author must be credited for his or her work.