Having seen the predominance of author catalogue, we need to know what constitutes authorship in the context of cataloguing. It is seen above that AACR-2 regards author as the person chiefly responsible for creating the intellectual content of a book. In other words the author is one who has conceived the ideas expressed in a book and desires to communicate them to others. It is then natural for a scholar and a cataloguer to ascribe a work to its creator.
In cataloguing, however, it is not only the principle of intellectual responsibility that operates but one is required to go beyond it. The term 'author' is taken in a much broader sense by a cataloguer. For a cataloguer, author is not just a person who writes a book, but also one who is otherwise responsible for the creation of the intellectual or artistic content of a book/work. This explains the existence of entries such as editors' commentators, compilers and translators under 'authors'. Although these are not the persons responsible for creating the original work, but they are yet responsible for bringing it out in a particular fowl for the first time. The different version of the original is thus the product of their intellection and therefore they are regarded as authors. Thus, the intellectual or artistic contents of a book may be the outcome of, the work by a single person or a group of persons or a corporate body.
Broadly speaking, authorship can be stated in two ways - personal authors, and corporate bodies responsible for the thought content of a work. In another sense, authorship can be of the following types, - single, shared responsibility and works produced by compilation or under editorial direction.