Most electric coffee grinders have a disc grinder: It consists of two concave discs, one of which is motorized while the other is permanently installed. A disc grinder requires faster rotations than a cone grinder, which generates more heat. A cone grinder grinds more gently because the coffee beans are crushed between the inner cone and the wall of the grinder. Many professionals therefore prefer it to a disc grinder. Baratza mainly uses cone grinders in its models, but also has some with disc grinders in its range.