Since a logo is the visual entity signifying an organization, logo design is an important area of graphic design. A logo is the central element of a complex identification system that must be functionally extended to all communications of an organization. Therefore, the design of logos and their incorporation in a visual identity system is one of the most difficult and important areas of graphic design. Logos fall into three classifications (which can be combined). Ideographs, such as Chase Bank, are completely abstract forms; pictographs are iconic, representational designs; logotypes (or word marks) depict the name or company initials. Because logos are meant to represent companies' brands or corporate identities and foster their immediate customer recognition, it is counterproductive to frequently redesign logos.