Over the years, clock styles have acquired names that represent some aspect of their design, function, material, region of origin or other characteristic traits. The categorization of a clock to a particular style is not always an easy black and white decision, and some clocks might fit in several style types (Belgium Black Marble is usually a Mantel Clock). To complicate the decision further, some styles may go by several names (Grandfather, Tall Case, Long Case, Hall Clock, Floor Clock). And some choices are certainly more obvious than others (Banjo and Cuckoo, which are both wall clocks). The decision of which style an individual clock has been assigned below is more a matter of personal opinion and "best fit" than an exact science.