I am delighted to see more educators engaging with OpenEducation or at least taking a greater interest in things "open" but I think it would be helpful to have a sort of beginner's guide to the many forms of open which are relevant to educators. I do not profess to be an expert in all things open but, as chair of the Open Education Special Interest Group and as an open education practitioner, I feel I could contribute a little to demystifying some of the terminology which comes under the banner "open". Here goes.
Probably the first term most academics engage with as it relates to academic publishing. Essentially this is a category of publication which is accessible to anyone rather than being restricted to those who are registered with a university. Some publishers require APCs (article processing fees) in order to make publications available to a wider public. For more detail see Jisc's useful guide. Librarians are often experts in this area.