Besides these sources of lexical knowledge, there are also sources of world knowledge in semi-formalized form, such as tabulations and gazetteers of various sorts, and “info boxes” in online knowledge resources such as Wikipedia (e.g., the entries for notable personages contain a box with summary attributes such as date of birth, date of death, residence, citizenship, ethnicity, fields of endeavor, awards, and others). But to the extent that such sources provide knowledge in a regimented, and thus easily harvested form, they do so only for named entities (such as people, organizations, places, and movies) and a few entity types (such as biological species and chemical compounds). Moreover, much of our knowledge about ordinary concepts, such as that of a tree or that of driving a car, is not easily captured in the form of attribute-value pairs, and is generally not available in that form.