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What is MARC?

Introduction to MARC Cataloging

MARC stands for MAchine-Readable Cataloging. A MARC record is a bibliographic record formatted specifically to be read and interpreted by a computer.

In a traditional card catalog, information was printed on cards and filed manually. MARC translates that card data into a digital database by pulling the information apart into categories called fields.

MARC Field Ranges (The 100s)

Fields are grouped by the type of information they contain:

  • 001–099: Fixed information, control numbers, and call numbers
  • 100s: Main Author/Entry information
  • 200s: Title, Edition, and Publication information
  • 300s: Physical description (pages, size, accompanying material)
  • 400s: Series statements (as they appear on the item)
  • 500s: Notes (General, contents, summary)
  • 600s: Subject access points (Authority-controlled terms)
  • 700s: Added entries (Co-authors, illustrators, performers)
  • 800s: Series added entries (Authorized forms)

The Anatomy of a MARC Field

Each field is subdivided into three parts: Tags, Indicators, and Subfields.

1. MARC Tags

The tag is the three-digit number identifying the field type (e.g., 245 for Title). In many systems, the tag is followed by two indicator spaces.

2. Indicators

Indicators are two character positions following the tag that provide specific instructions to the computer. For example, in the Title field (245):

  • First Indicator 1: Means a separate title entry should be made.
  • Second Indicator 4: Tells the computer to ignore the first 4 characters (e.g., "The ") when alphabetizing.

3. Subfields

Subfields are smaller pieces of data within a field, marked by delimiters (usually a $ or ).
Example: 245 14 $a The color purple / $c Alice Walker.

  • $a: Main Title
  • $h: GMD (Format)
  • $c: Statement of Responsibility (Author)

Authority Control

To prevent confusion, fields like 1XX (Names) and 6XX (Subjects) are under Authority Control. This ensures a consistent form is used for every entry (e.g., "Washington, George, 1732-1799" is used every time rather than variations).

The Fixed Fields (007 and 008)

These fields contain coded data about the item's physical characteristics and language.

Common 007 Field Codes for A/V Materials
Material TypePosition 1 (Category)Position 2 (Specific Material)
DVD / Blu-rayv (video)d (videodisc)
Music CD / Book on CDs (sound recording)d (sound disc)
CD-ROMc (electronic resource)o (optical disc)

Training Resources

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