Degrees of Open
A review of definitions and explanations of openness
Types of open
The word 'open' can mean different things to different people and can vary depending on context.
To the Canadian government's Canada School of Public Service, open refers to learning offered online.
To some universities, open refers to the continuing education options they offer to students who may not be registered in specific programs. The University of Guelph refers to open in the context of the Open Learning and Educational Support they provide through their OpenEd page.
Some people interpret open as meaning free of cost or free of restrictions. Libre (the French word for open as in freedom) is often used to emphasize that a resource is open to use, repurpose, or share with others. Therefore open (or libre) may refer to the type of copyright (or lack thereof) that defines what you can do.
Final thought: Open can be free of cost or low cost. Things that are free may not be open.