Cataloging Resources

More than you ever wanted to know about cataloging and classification.


Are there cataloging topics that should be included here and are not? Are there links that you find useful in your cataloging that have been left out of this resource? Contact Mary Russell with suggestions to improve this page.

MARC Records

The MARC 21 formats are standards for the representation and communication of bibliographic and related information in machine-readable form. MARC 21 is maintained by the Library of Congress. OCLC-MARC is OCLC's implementation of MARC 21. Records available for download from the NHAIS ILL System come from OCLC's WorldCat and consequently are in OCLC-MARC.

Here are a few resources that may be useful to you in working with MARC records:

The MARC Standards page, maintained by the Library of Congress Network Development and MARC Standards Office, is the authoritative source for all things MARC. It includes background information, listings of changes that have been made over the years, and links to the committees that suggest and implement changes to the MARC 21 formats.

If you want a quick, simplified overview of the MARC format this is a good resource: Understanding MARC Bibliographic: Machine Readable Cataloging.

While OCLC-MARC follows MARC 21 closely, there are differences. The authoritative source on OCLC-MARC is OCLC Bibligraphic Formats and Standards. This is the source you should consult for questions about records from NHU-PAC. If you really want to get into the nitty-gritty of the differences between OCLC-MARC and MARC 21 see MARC 21 Bibliographic Data Elements not Implemented by OCLC.

Cataloging Standards

The Anglo-American Cataloguing Rules (AACR) are designed for use in the construction of catalogs and other lists in general libraries of all sizes. The rules cover the description of, and the provision of access points for, all library materials commonly collected at the present time. AACR2 was first published in 1978 and has been updated many times by the JSC. It is largely designed for an environment dominated by the card catalog. The International Conference on the Principles and Future Development of AACR that was held in Toronto in 1997 identified substantive problems with AACR2. Although the updates issued in the years following that conference (which brought us up to the current edition, AACR2r) addressed some of these problems, it became clear that a fundamental rethinking of the code was required to respond fully to the challenges and opportunities of the digital world. Yale University has created an extensive resource on AACR2 and all things related.

RDA stands for "Resource Description and Access" and is the working title of the new standard that is expected to be the successor to AACR2. In April 2005, the Joint Steering Committee for the Revision of AACR (JSC) determined from comments received on the revision of part I of AACR3 that they needed to change their approach. It was decided that a new standard designed for the digital environment was more appropriate. Their vision included guidelines and instructions that would cover description and access for all digital and analog resources, resulting in records that could be used in a variety of digital environments (the Internet, Web OPACs, etc.)

The International Standard for Bibliographic Description (ISBD) dates back to 1969, when IFLA sponsored an International Meeting of Cataloguing Experts which produced a resolution that proposed creation of standards to regularize the form and content of bibliographic descriptions. As a result, the Committee on Cataloguing put into motion work that ultimately would provide the means for a considerable increase in the sharing and exchange of bibliographic data. This work resulted in the concept of the International Standard Bibliographic Description (ISBD), which has now endured for more than 30 years. The individual formats to which the ISBD concept has been applied (like AACR2) are now used by bibliographic agencies, national and multinational cataloging codes, and catalogers in a wide variety of libraries throughout the world, because of their potential for promoting record sharing.


The Dewey Decimal Classification (DDC) system, devised by library pioneer Melvil Dewey in the 1870s and owned by OCLC since 1988, provides a dynamic structure for the organization of library collections. In its 22nd edition in 2010, and available in print and Web versions, the DDC is the world's most widely used library classification system. OCLC is the authority on DDC, but there are resources like Let's Do Dewey and the monster Dewey tutorial that have been created by libraries who use the system. If you need more Dewey in your life, check out 025.431: The Dewey Blog.

The Library of Congress Classification (LCC) is a classification system that was first developed in the late nineteenth and early twentieth centuries to organize and arrange the book collections of the Library of Congress. As you would expect, it is maintained by the Library of Congress. Quarterly the Library of Congress publishes the Cataloging Services Bulletin which includes information about how LC has applied the classification rules and details on various classification and cataloging issues.

The Superintendent of Documents (SuDocs) classification system is designed to group together publications by the same government author. It was developed in the Library of the Government Printing Office between 1895 and 1903. There is a nice, simple overview of SuDoc numbers (for people who want to use them, not assign them) from the NCSU Libraries.

The OCLC Classify project provides a quick and easy way to see what other libraries have chosen as a classification for specific titles. You can search by title and see what DDC numbers and what LC Class has been used most frequently for that title. You can also see what alternate numbers have been used. After searching for a number this way be sure to check the number in your classification schedules and against your own collection to verify that it makes sense in your library's collection!


A cutter number, sometimes called an author or book number, is a combination of letters and numbers appended to a classification number to maintain the alphabetical order of items within a single classification. Cutters may be as simple as the first few letters of the author's name, or may be generated using a cutter table. The Cutter-Sandborn Three-Figure Author Table is used by many libraries including Yale University and Harvard. The tables are named for Charles Ammi Cutter.

OCLC has a free downloadable Dewey Cutter program that can be used to generate cutters from the OCLC Four-Figure Cutter Tables which is much simpler than building them from a table. This is the resource that NHSL uses to create cutters for our collections.

Cataloging Services

MARC records

NHAIS member libraries can use Z39.50 to search for and download MARC records from the NHAIS ILL System into their local system or a Z39.50 client at no charge. Z39.50 connection details are included in Options for Downloading MARC Records from NHU-PAC

Copy cataloging

For items not found in the NHU-PAC NHAIS member libraries can enter brief record requests using the Brief Records form and we will locate an appropriate MARC record, either in the NHU-PAC or from OCLC, and add it to the NHU-PAC so it can be downloaded via Z39.50 or directly through the NHAIS ILL System if you are a participating library.

Subject Headings

Library of Congress Subject Headings are currently in the 31st edition (2010) and are available in various forms (for purchase) from the Library of Congress Cataloging Distribution Service. Lists of new and changed subject headings are posted on the Cataloging Policy and Support Office web site as they are approved. There is a free, searchable database of LC headings or they are accessible (for free) in the LC Authority File.

The Sears List of Subject Headings a product of the H.W. Wilson Co. has served the needs of small and medium-sized libraries, delivering a basic list of essential headings, together with patterns and examples to guide the cataloger in creating further headings as needed. It was developed in the 1920s by Minnie Earl Sears.

MeSH is the National Library of Medicine's controlled vocabulary thesaurus. It consists of sets of terms naming descriptors in a hierarchical structure that permits searching at various levels of specificity.

Standard Numbers

The International Standard Book Number (ISBN) is a 10-digit number that uniquely identifies books and book-like products published internationally. Its purpose is to establish and identify one title or edition of a title from one specific publisher and is unique to that edition, allowing for more efficient marketing of products by booksellers, libraries, universities, wholesalers and distributors. In the United States ISBNs are the responsibility of R.R. Bowker. On January 1, 2005 the book industry began the transition process to the 13-Digit ISBN.

The International Standard Serial Number (ISSN) is a code used on catalogs, databases or commercial transactions each time serial publications are involved. In the United States ISSNs are assigned by the Library of Congress.

The LCCN is a unique number assigned to each Library of Congress catalog record and strictly speaking identifies the bibliographic record, not the item that record represents. When card catalogs were the prevalent format of bibliographic records LCCN stood for "Library of Congress Card Number." Now that most bibliographic records are displayed and distributed through online automated systems, it is more accurate to use the term "Library of Congress Control Number." Related, but not exactly the same, is the Preasigned Control Number (PCN) which is a Library of Congress Control Number which has been "preassigned" to a given work prior to the work's publication.

Miscellaneous Tools

Similar to our document on Developing Your ILL Policy, NHAIS has created Developing a Local Cataloging Policy to walk you through the questions that you will need to address when creating a written policy to document your local cataloging decisions.

There is a very helpful video from the Rod Library at the University of Northern Iowa on How to Use a Natural Scale Indicator to calculate the scale on a map when only a bar scale is printed on the map.

The NH State Library collects a variety of books on cataloging and classification and makes them available to NH libraries via ILL. Using the Advanced Search feature and limiting your search to the "LIS Collection" will help you locate these items.