Cataloging or Cataloguing or Library Cataloging is the process of creating and maintaining bibliographic and authority records in the library catalog, the database of books, serials, sound recordings, moving images, cartographic materials, computer files, e-resources etc. that are owned by a library. The catalog may be in tangible form, such as a card catalog or in electronic form, such as online public access catalog (OPAC). Relative to the movement of materials within technical services, cataloging usually follows the receipt of ordered books in acquisitions. The process of cataloging involves three major activities, namely, Descriptive Cataloging, Subject Cataloging, and Authority Control.
In libraries, metadata creation is often called cataloging¹.
Cataloging is a subset of the larger field called information organization.
It can be defined as, “The process of creating metadata for resources by describing a resource, choosing name and title access points, conducting subject analysis, assigning subject headings and classification numbers, and maintaining the system through which the cataloging data is made available.”–Joudrey, Taylor, and Miller (2015). Introduction to Cataloging and Classification, 11th ed., Santa Barbara, CA: Libraries Unlimited.
In other words, it is the process of creating metadata about library resources, which is included in the catalog.
A catalog is an organized compilation of bibliographic metadata that represents the holdings of a particular institution or a library network and/or resources accessible in a particular location.
Cataloging, traditionally, has been seen as comprising two specific activities: Descriptive Cataloging and Subject Cataloging.
DESCRIPTIVE CATALOGING
Descriptive Cataloging or Descriptive Cataloguing includes recording the attributes of a library item, such as the name of author(s), contributor(s), title, edition, publisher, distributor, date, the number of pages, its size, name of series, etc. Descriptive Cataloging enables the user to find and identify a book, by the name of the author, the title, variant titles, etc. Two popular standards for Descriptive Cataloging are Anglo-American Cataloging Rules (AACR) and its successor Resource Description and Access (RDA).

Anglo-American Cataloguing Rules (AACR, AACR2, AACR2R) – Anglo-American Cataloguing Rules (AACR) is the essential international cataloguing code used for descriptive cataloging of various types of information resources by libraries in the United States, Great Britain, Canada, and Australia as well as in many other countries. It was first developed in 1967 and updated regularly until 2005. The revisions and updates of the standard are referred to as AACR2. The second edition of Anglo-American Cataloguing Rules (AACR2) is the most widely used cataloging code, designed for use in the construction of catalogs and other lists in general libraries of all sizes. AACR2 comprise a detailed set of rules and guidelines for producing metadata in a surrogate record to represent a library resource. The rules cover the standard description of areas like, the title, publisher, edition, series, etc., as well as the provision of choice and form of access points (headings) for all materials which a library may hold or to which it may have access, including books, serials, cartographic materials, electronic resources, etc. AACR also provides rules for the formulation of standard forms of names and titles to provide access to and grouping of those descriptions. AACR2 standardized cataloging and ensured consistency within the catalog and between the catalogs of libraries using the same code in describing the physical attributes of library materials identically. AACR marked a shift from the previous cataloging rules, which were criticized for being too detailed, complex, and mere compilations of rules to handle specific bibliographic cases. Anglo-American Cataloguing Rules are considered as the most important advances in English-language codes for descriptive cataloging during the twentieth century.

Resource Description and Access (RDA) – RDA stands for “Resource Description and Access” and is the title of the standard, that is the successor to AACR2. Resource Description and Access (RDA) is a standard for descriptive cataloging providing instructions and guidelines on formulating bibliographic data. Resource Description & Access (RDA) is a set of cataloging instructions based on FRBR and FRAD, for producing the description and name and title access points representing a resource. RDA offers libraries the potential to change significantly how bibliographic data is created and used. RDA is a standard for resource description and access designed for the digital world. It provides (i) A flexible framework for describing all resources (analog and digital) that is extensible for new types of material, (ii) Data that is readily adaptable to new and emerging database structures, (iii) Data that is compatible with existing records in online library catalogs. RDA is a package of data elements, guidelines, and instructions for creating library and cultural heritage resource metadata that are well-formed according to international models for user-focused linked data applications. RDA goes beyond earlier cataloging codes in that it provides guidelines on cataloging digital resources and places a stronger emphasis on helping users find, identify, select, and obtain the information they want. RDA also supports the clustering of bibliographic records in order to show relationships between works and their creators.

Janis L. Young and  Daniel N. Joudrey¹ describe Descriptive Cataloging as below:

Descriptive Cataloging

• Identification of the resource
• Description of the resource
• Access points for names and titles
• Authority work for names and titles

Descriptive cataloging is that phase of the cataloging process that is concerned with the identification and description of an information resource, answering questions such as:

• What is it?
• What are its distinguishing and significant characteristics?

It is also concerned with encoding this information for machine processing, for example in:

• A MARC record,
• An XML encoded description, or
• A metadata statement compatible with linked data principles.

It is also concerned with the selection of names and titles useful for providing access to the resources and the establishment of authorized access points for names and titles, answering questions such as:

• What is it called?
• Who is responsible for its creation?
• Who else contributed to it?
• By what form of name or title are they best known?

Descriptive cataloging describes the makeup of an information resource and identifies those entities responsible for its intellectual and/or artistic contents without reference to its classification by subject or to the assignment of subject headings, both of which are the province of subject cataloging.

SUBJECT CATALOGING
Subject Cataloging (or Subject Cataloguing) involves the subject analysis of the resource and providing corresponding subject headings from a controlled vocabulary or subject heading list, such as Library of Congress Subject Headings (LCSH), Medical Subject Headings (MESH) and assignment of classification numbers using schemes such as Library of Congress Classification (LCC) or Dewey Decimal Classification (DDC).
Subject Heading is defined as the most specific word or group of words that capture the essence of the subject or one of the subjects of a book or other library material which is selected from a subject heading list containing the preferred subject access terms (controlled vocabulary) and assigned as an added entry in the bibliographic record which works as an access point and enables the work to be searched and retrieved by subject from the library catalog database. Classification or Library Classification is the process of arranging, grouping, coding, and organizing books and other library materials on shelves or entries of a catalog, bibliography, and index according to their subject in a systematic, logical, and helpful order by way of assigning them call numbers using a library classification system, so that users can find them as quickly and easily as possible. Use of classification enables library users to browse on shelves to find its materials, determines the place of a book and the shelf, and also collocates additional items on the same or related subjects. Classification also enables the library users to find out what documents the library has on a certain subject. The cataloger assigns a classification, or call number, in correlation with the subject headings.

Janis L. Young and  Daniel N. Joudrey¹ describe Subject Cataloging as below:

Subject cataloging is the phase of the cataloging process which is concerned with determining and describing the intellectual or artistic content and the genre/form characteristics of a resource, and translating that understanding into subject headings and classification notations.
After the resource’s aboutness has been determined, as many subject headings as are appropriate are chosen from a standard list. There are many such lists, including: Library of Congress Subject Headings (known as LCSH), the LC Genre/Form Terms for Library and Archival Materials, Medical Subject Headings (which is often referred to as MeSH), the Art and Architecture Thesaurus, and so on.
In addition, a classification notation is chosen from whatever classification scheme is used by the library. In the United States, the most likely candidates are the Library of Congress Classification (often referred to as LCC) or the Dewey Decimal Classification (known as DDC).
Traditionally in the U.S., the classification serves as a means for bringing a resource into close proximity with other resources on the same or related subjects. In the case of tangible resources, the classification is the first element of the call number, which is a device used to identify and locate a particular resource on the shelves.

Subject Cataloging Phases

• Two Phases of Subject Cataloging

• • Conceptual analysis
    • What is it about?
    • What is its form or genre?

• • Translation
    • Controlled vocabulary terms
    • Classification

1. Janis L. Young and  Daniel N. Joudrey, Library of Congress, “Library of Congress Subject Headings: Online Training,” https://www.loc.gov/catworkshop/lcsh/index.html (accessed March 17, 2020).