jQuery's extreme ubiquity arguably makes it the de facto DOM abstraction library, and this does conform to the definition. Its demographic, or target audience,

jQuery's extreme ubiquity arguably makes it the de facto DOM abstraction library, and this does conform to the definition. Its demographic, or target audience, is irrelevant, because it is everywhere, and much to the detriment of 'pure javascript' (some might argue). It'll remain that way until differing browser implementations converge and obviate the need for an abstraction that papers over the cracks.