MARC 21 Format for Classification Data

This online publication provides access to a complete and concise version. The "complete" taxonomy format includes a detailed description of each data element, an example, an entry rule, and a history section. The "concise" taxonomy format contains a brief description and example of each data element. In the title of the description of each field, a complete and concise version is stated.

Changes to the MARC 21 classification data format generated by update number 26 (April 2018) are displayed in red. The full title date for each field indicates the last month and year of the update.

MARC (MAchine-Readable Cataloging) is a bibliographic data format. It was developed in the United States in 1966. Since that time, the MARC 21 version has been used in libraries around the world. MARC 21 is a common format that can be read and processed by various applications. Its main purpose is to transfer bibliographic data between libraries.

The purpose of including the class number in the PCC record is to provide classified access and to provide a basis for establishing a dialing number via one of the classification systems supported by MARC 21. The category number provided is intended to be the most useful form among the broadest potential users of the classification system. Several classification systems distinguish between generic and specific ones. Generics related to generic drugs can group items with similar knowledge content (class number). Specific relevant data allows personalizing items and allowing them to be finely placed within a group (eg, author Cutter, work Cutter, etc.). When applying such a system to PCC records, only one class number is required. The PCC library always has the option to provide a complete phone number, but this is not a program requirement.

For a long time, libraries have tried to maintain common standards for cataloging and subject classification. With the advent of automation, the MARC (machine readable catalog) format provides domestic and international standards on how to transfer catalog records from one machine to another machine. Along with another important library automation standard called Linking System Protocol, basically library users can easily access their library records, as well as easily access records from many remote library systems will do so. .

Finally, the data exchange standard is the key to modern library catalog standards. These allow the library to reliably and consistently exchange metadata. A standard such as MARC 21 means that the library that sends the data always includes the header information of the library that receives the data in the title element. Furrie (2009) explains how MARC achieves this goal. "The catalog card information can not be entered into the computer automatically to create a catalog.The computer needs a way to interpret the catalog record information.The MARC record contains data before each bibliographic information A guide or a small "road map" is included. .