MARC 21 Concise Authority: Introduction

This is an ARCHIVED VERSION of the 2005 electronic edition of the MARC 21 Concise Formats. Please see www.loc.gov/marc/concise/ for the most up-to-date version of the electronic MARC 21 Concise Formats.

The MARC 21 Format for Authority Data is designed to be a carrier for information concerning the authorized forms of names and subjects to be used as access points in MARC records, the forms of these names, subjects and subdivisions to be used as references to the authorized forms, and the interrelationships among these forms.

A name may be used as a main, added, subject added, or series added access entry. The term name refers to:

A subject may be used only as a subject access entry. The term subject refers to:

The MARC 21 Format for Authority Data also provides authoritative information concerning the standard terms used as node labels in the systematic section of a thesaurus to indicate the logical basis on which a category has been divided. A node label is not assigned to documents as an indexing term.

Information for Translators and Other Users
Items highlighted in red indicate changes made after the 2004 edition of the MARC 21 Concise Formats was published and are included in the 2005 printed edition of the MARC 21 Concise Formats.

Kinds of Authority Records

MARC authority records are distinguished from all other types of MARC records by code z (Authority data) in Leader/06 (Type of record). The MARC 21 Format for Authority Data further identifies seven kinds of authority records in 008/09, Kind of record:

Established heading (Code a)
A record in which the 100-155 fields contain established headings. An established heading record may also contain tracing fields for variant and related headings and notes recording such information as the sources used to establish the heading and series treatment.

Reference (Code b or c)
A record in which the 100-155 fields contain unestablished headings. The record also contains either a 260 (Complex See Reference Subject), a 664 (Complex See Reference Name), or a 666 (General Explanatory Reference Name) field to guide the user to an established heading. Separate codes are defined in 008/09 for traced and untraced reference records. The distinction depends upon whether the 1XX heading in the record is also traced as a 4XX see from tracing in an established heading record.

Subdivision (Code d)
A record in which the 18X field contains an unestablished partial heading that is meant to be used as a subject subdivision part of an established heading.

Established heading and subdivision (Code f)
A record in which the 15X field contains an established heading that may also be used as a subject subdivision with another established heading. (An organization may choose to create instead separate established heading and subdivision records.)

Reference and subdivision (Code g)
A record in which the 15X field contains an unestablished heading that may be used as a reference term and as a subject subdivision with an established heading. (An organization may choose to create instead separate reference and subdivision records.)

Node label (Code e)
A record in which the 150 field contains a term that is meant to be used in the systematic section of a thesaurus to indicate the logical basis on which a category has been divided. The term is not an established heading and is not assigned to documents as an indexing term.

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Typographical Conventions

Throughout this document, the following typographical conventions are used:

0 - The graphic 0 represents the digit zero in tags, fixed-position character position citations, and indicator positions. This character is distinct from an uppercase letter O used in examples or text.

# - The graphic symbol # is used for a blank (hex 20) in coded fields and in other special situations where the existence of the character blank might be ambiguous.

$ - The graphic symbol $ is used for the delimiter (hex 1F) portion of a subfield code. Within the text, subfield codes are referred to as subfield $a, for example.

/ - Specific character positions of fixed-length data elements, such as those in the Leader, Directory, and field 008, are expressed using a slash and the number of the character position, e.g., Leader/06.

1 - The graphic 1 represents the digit one (hex 31). This character must be distinguished from a lowercase roman alphabet letter l (el) (hex 6C) and the uppercase alphabetic letter I (eye) (hex 49) in examples or text.

| - The graphic | represents a fill character (hex 7C).

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Organization of the Electronic Version of the Concise Format

This electronic concise format is organized into parts that generally mirror the tabbed sections of the full printed format documentation. Each part is divided into chapters that usually cover a single field and all of the data elements possible within it (that is, character positions for fixed-length fields and indicators and subfield codes for variable length fields). The Leader and the Directory are described in the first main part, followed by parts containing the variable control fields and variable data fields arranged in numerical field tag order.

Obsolete and deleted content designators are not listed. They are found in the full printed version of the format and in the electronic MARC field lists.

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