So I see on a lot of people's resumes they list AJAX in their technologies (or programming languages - and I recognize that it is not a language). To me, AJAX seems like such a small concept to be individually listed. It seems it is almost as useful as listing MVC experience (because MVC too is a concept), which is good to know, but AJAX, like MVC, is just a facet of one's abilities as a developer. However, saying "I know AJAX" seems like it is much smaller thing than saying "I know MVC".
What does saying "I know AJAX" actually cover?
The wikipedia page on AJAX lists just a few more things, but I'd love to ask the community... am I missing a key concept about AJAX? If not, it seems like that listing it on a resume is just fluff.