There are two different views as to whether all traits exist in all people and one (1) of them is Idiographic - people have unique personality structures; thus some traits (cardinal traits) are more important in understanding the structure of some people than others. The Idiographic view emphasizes that each person has a unique psychological structure and that some traits are possessed by only one person; and that there are times when it is impossible to compare one person with others. This viewpoint also emphasizes that traits may differ in importance from person to person (cardinal, central and secondary traits). It tends to use case studies, bibliographical information, diaries, and others for information gathering. This approach is in contrast to the Nomothetic Approach, which instead emphasizes the general laws that apply to all individuals.