When our current catalogs were set in motion in 1876, there were few other bibliographic tools. Poole’s index appeared occasionally and then Wilson’s Reader’s Guide made its appearance at the beginning of the 20th century but, for most libraries, the catalog played a prime role in providing access to bibliographic information. Catalogs were published in book form and shared among libraries with larger libraries developing extensive collections of the catalogs of other libraries. The twentieth century saw the publication of many subject-specific bibliographies but it wasn’t until the middle part of the century that indexing of the periodical literature really took off.
The second half of the twentieth century saw the library catalog playing proportionally smaller role in bibliographic searching. By bibliographic searching, I do not mean the search for bibliographic records as we do in technical services operations but rather the search for citations to documents that underlies our use of catalogs and bibliographic databases. The library catalog’s chief utility was in identifying individual monographs owned by individual or groups of libraries. Each catalog did this for a limited number of libraries although the largest did it for thousands of libraries and came to be known as “WorldCat.”
Over the course of the 20th century, libraries found ways to do proportionately less and less creation of bibliographic records. By the end of the century, for most libraries, most records that enter the catalog are created by some other source, often the US Library of Congress. Because the catalog continued to limit its contents to items “held” by a library, a complex system developed for choosing and downloading individual cataloging records. Since the information explosion was under way and, as Ranganathan specified, “The library is a growing organism,” the cataloging operation continued as a major function in many libraries.
From the standpoint of the folks who do it (catalogers) and library administrators, the catalog differs greatly from other bibliographic databases. It’s chief differences are two: 1) It limits its scope by library holdings, and 2) it’s done in-house. There are advantages and disadvantages associated with these two characteristics.
As the 20th century came to an end and the 21st century began, the role of the catalog as bibliographic retrieval device continues to diminish in proportion to other retrieval devices.. A revolution approaches that requires a wholly new way of looking at bibliographic retrieval by those who are now involved with cataloging.
[A lousy place to break this off, but bear with me. It's time to go congratulate our local graduates and welcome them to our profession!]