Forms of Centralisation 

In centralised cataloguing we observe that there are several forms of centralisation like: 

1. Card (or Sheaf) service 
2. MARC (Machine-Readable Catalogue) service 
3. Information service 
4. Cataloguing-in-Source 
5. Cateloguing-in-publication 
6. Pre-natal Cataloguing 

Card (or Sheaf) Service 

This is the type of centralised cataloguing where the unit entries are prepared by a central organisation. The individual libraries can buy these cards in multiple numbers. One card is retained as main entry and,other cards are used for preparing added entries by adding the appropriate access points like names of the collaborator(s),,title(s), subject(s), etc. The BNB, the Library of Congress and the H.W. Wilson Company are rendering such type of service. 

MARC Service 

In this service cataloguing data is prepared for documents in machine readable form on magnetic tapes, etc. Client libraries can either directly search the information from the tapes or use the service for the creation of conventional forms of catalogues and bibliographies. In Unit 9 of this Block you will learn more about MARC and computer catalogues. Information Service In this type of centralised service a central organisation produces a bibliography from which libraries can prepare their own catalogues. These catalogues can be prepared either by using the catalogue information from the bibliography for the books they have to catalogue or by cutting and pasting on cards the appropriate entries from the bibliography. The British National Bibliography (BNB) and the Indian National  Bibliography (BNB) are such types of tools. 

Cataloguing-in-Source 

A publisher of a book, if he can provide the catalogue entry in the book itself, will be helping the purchasing libraries. Their processing work is reduced to a large extent. What is needed in such service is that the catalogue code followed should be the one which is universally acceptable. The entry should also carry class number according to a popular and acceptable scheme of classification. Such a service is known as Cataloguing-In-Source (CIS). 

Ranganathan made a plea from such cataloguing of a book even before its release. He termed it as 'Pre-natal Cataloguing'. There is yet another term for similar service; namely, Cataloguing-in-Publication (CIP).