Open Access: A Guide

Different open access types are currently commonly described using a color system. The most commonly recognized names are "green", "gold", and "hybrid" open access; however, a number of other models and alternative terms are also used.

There are two primary vehicles for delivering OA to research articles, OA journals ("gold OA") and OA repositories ("green OA").

• The chief difference between them is that OA journals conduct peer review and OA repositories do not. This difference explains many of the other differences between them, especially the costs of launching and operating them.