The description includes a thorough listing of physical characteristics, including variation in these that the scientist has observed in the population. These proceed from general to specific (e.g. first describing overall shape and size, then proceeding to describe each body part in more detail) and pay special attention to those characteristics that can be used to distinguish it from other species. The description needs to be both scientifically objective and visually vivid, which means that writing it “combines two of the most difficult types of writing: the technical description and the poem” (Winston). The conventions for different taxa ( International Code of Nomenclature for algae, fungi, and plants (ICN), the International Code of Zoological Nomenclature (ICZN), or the International Code of Nomenclature of Bacteria (ICNB)) provide vocabularies and specialized terminologies that are used in those fields.