The chart below is a very simplified and abbreviated overview of the scope of the field, delineated in terms of settings where information work is performed, for whom, and for what purpose. Succeeding pages give you an idea of how the range of occupations within the field can be described, some views of the knowledge base of the field, and some miscellaneous ruminations. This section of the packet, as they say of web pages, is very much "under construction!"
When you look at the long list of specializations, practice settings, and professional associations, you begin to realize how diverse and fragmented this field can be. This state of affairs is both an asset and a hazard: On the one hand, you have a wide arena in which to find your own particular niche, but on the other hand, it will be hard to define your profession to an outsider!
Until recently, one of the most significant fissures was between librarianship and information science. The former was tied to institutional affiliations and focused on a subject or a client group, whereas the latter tended to revolve first around technology and then around information as entity. One definition of information science states:
IS is centered on the representation, storage, transmission, selection (retrieval, filtering), and the use of documents and messages, where documents and messages are created for use by humans. Interest extends outwards in many directions because of the need to understand the contextual, institutional, methodological, technological, and theoretical as pects. [Michael K. Buckland and Ziming Liu, "History of Information Science" in Annual Review of Information Science and Technology, vol. 30, 1995, p.385.]
This definition pretty well describes our MLS curriculum, so you can see why some of us feel that the erstwhile gulf between librarians and information scientists is fast disappearing! We are all interested basically in the same phenomena -- but the emphases and contexts will vary.