A burr grinder is one that breaks up beans by crushing them, like a mill. (A blade grinder chops beans with, well, a blade). Burr grinders are said to cut beans more precisely and evenly, delivering better flavor. Within the burr world, there are two kinds of grinders: conical and flat. A conical burr grinder has a cone-shaped center burr and outer serrated burr; a flat one features two round, facing burrs that turn out grinds that are even more precise than their conical brethren (but they also make more noise).