Good point, Gilbert. Even I use the term learning, when I should be using training, instruction or education; and I know better ;-)

However, I think that you could add the term "environment" to each of these terms and they could describe a continuum that might be useful for design considerations. A formal learning environment might be a course, while informal learning environments are all around us. A non-formal learning environment would be an intentional grouping of people who have some learning objective(s) in mind.