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MARC 21 LITE Bibliographic
April 2008

Introduction to MARC 21

The MARC 21 Format for Bibliographic Data is designed to be a carrier for bibliographic information, such as titles, names, subjects, notes, publication information, and physical descriptions of items. The MARC 21 Format for Bibliographic Data contains data elements for the following types of material:

Books - textual items, monographic in nature, that are in bound book, electronic, or microform.

Continuing resources- textual items with a recurring pattern of publication, e.g., periodicals, newspapers, yearbooks.

Computer files - computer software, numeric data, computer-oriented multimedia, online systems or services. Other types of electronic resources are coded for their most significant aspect, such as textual ("books" or "serials"), cartographic ("maps"), etc.

Maps - all types of cartographic materials, including sheet maps and globes in printed, manuscript, electronic, and microform.

Music - printed and manuscript notated music

Sound recordings - nonmusical sound recordings, and musical sound recordings.

Visual materials - images and objects, e.g., projected media, motion pictures, two-dimensional graphics, three-dimensional artifacts, naturally occurring objects.

Mixed materials - primarily archival and manuscript collections of a mixture of forms of material.

The MARC 21 LITE Bibliographic Format is a subset of the markup defined in the full MARC 21 Bibliographic Format. It includes all essential data elements that are needed to create bibliographic descriptions of information items. It is a true subset of the data elements in the complete MARC 21 Format for Bibliographic Data and does not collapse or change any data tagging found in the full format. Records using only the elements in this document are valid MARC records and may be integrated with fuller records without alteration. If elements from the full format are needed for special reasons in an implementation, they can always be added to LITE records by the implementer or user.

The MARC 21 LITE Bibliographic Format provides a quick reference guide to tagging. Where needed, it includes a concise description of each field, each character position of the fixed-length data element fields, and of the defined indicators in the variable data fields. Descriptions of subfield tags and coded values are given only when their names may not be sufficiently descriptive. Examples are included for each field.


A MARC record is composed of three elements: the record structure, the tagging and other content designation, and the data content of the record. The record structure is an implementation of ISO 2709, Information and Documentation - Format for Information Exchange. The content designation is the set of tags and codes that identifies and further characterize the data elements within a record and support the manipulation of the data content. The content of the data elements that comprise a MARC record is usually defined by standards outside the formats, such as cataloging rules, classification schemes, subject thesauri, code lists, or other conventions used by the organization that creates a record. The content of certain coded data elements (e.g., the Leader, and field 008) is defined in the MARC formats themselves.

The MARC record structure consists of three main components: the Leader, the Directory, and the Variable Fields. The following information summarizes the components of a MARC record. More detail is provided in MARC 21 Specifications for Record Structure, Character Sets, and Exchange Media.

Contains data elements that provide basic information about the item and information for the processing of the record. The data elements contain numbers or coded values and are identified by relative character position. The Leader is fixed in length at 24 character positions and is the first field in all MARC records.
Contains a series of entries that contain the tag, length, and starting location of each variable field within a record. Each entry is 12 character positions in length. The Directory entry for the Record Control Number (001) appears first. Subsequent entries for variable data fields follow, arranged in ascending order according to the first character of the tag. The stored sequence of the variable data fields in a record is not necessarily the same as to the order of the corresponding Directory entries. The Directory ends with a field terminator character (ASCII 1E hex).
Variable fields
The data in a MARC 21 record is carried in fields that may be variable in length, each identified by a three-character numeric tag that is stored in the Directory entry for the field. Each field ends with a field terminator character. The MARC record ends with a record terminator (ASCII 1D hex). There are two types of variable fields:
Variable control fields
The 00X tagged fields. The variable control fields are structurally different from the variable data fields. These fields do not contain indicator positions or subfield codes. They may contain either a single data element or a series of fixed-length data elements identified by relative character position.
Variable data fields
The 01X-8XX tagged fields

Within variable data fields, the following two kinds of content designation are used:

Indicator positions
The first two character positions at the beginning of each variable data field that contain values which interpret or supplement the data found in the field. Indicator values are interpreted independently, that is, meaning is not ascribed to the two indicators taken together. Indicator values may be a lowercase alphabetic or numeric character. A blank (ASCII 20 hex), represented in this document as a pound symbol (#) , is used in an undefined indicator position. In a defined indicator position, a blank may be assigned a meaning, or may mean no information provided.
Subfield codes
Two characters that precede each data element within a field that requires separate manipulation. A subfield code consists of a delimiter (ASCII 1F hex), represented in this document as a dollar symbol ($), followed by a data element identifier. Data element identifiers are lowercase alphabetic or numeric characters. Subfield codes are defined independently for each field; however, parallel meanings are preserved where possible. Subfield codes are defined for purposes of identification. The order of subfields is generally specified by external standards for the data content, such as the cataloging rules, not by this format.

Type of Record

A key data element in the record Leader is the type of item being described in the record. Leader/06 (Type of record) identifies the following item types.

Language (textual) material Nonmusical sound recording
Manuscript (textual) language material Musical sound recording
Computer file Projected medium
Cartographic material Two-dimensional nonprojectable graphic
Manuscript cartographic material Three-dimensional artifact or natural objects
Notated music Kit
Manuscript music Mixed material

Field and Subfield Repeatability

Theoretically, all fields and subfields may be repeated. The nature of the data, however, often precludes repetition. For example, a record may contain only one 1XX field; a bibliographic field 100 may contain only one subfield $a (Personal name), but may contain more than one subfield $c (Titles and other words associated with a name). Field and subfield repeatability/ nonrepeatability is indicated by (R) or (NR) following each field and subfield name.

Fill Character and Related Values

A fill character (ASCII 7C hex), represented in this document as a vertical bar (|), may be used in a record when the format specifies a code to be used but the creator of the record decides not to attempt to supply a code. A fill character may not be used in any character position of the leader or tags, indicators, or subfield codes.

Code u (Unknown or unspecified), when it is defined, is used to indicate that the creator of the record attempted to supply a code but was unable to determine what the appropriate code should be.

Code n (Not applicable), when it is defined, is used to indicate that the characteristic defined by the position is not applicable to a specific type of item or kind of record.

Display Constants

A display constant is a term, phrase, and/or spacing or punctuation convention that may be system generated in order to make a visual presentation of data in a record more meaningful to a user. The display text is not carried in the record but an indication for it, based on tags, indicators, subfield codes, or coded values, is. Suggested display constants and display examples are provided. The use and display of these constants is determined by each organization or system.



In general, the responsibility for the data content, content designation, and transcription of data within a MARC 21 record may be determined by examination of the field indicated in field 040 (Original Cataloging Agency).

In unmodified records, the organization identified as the original cataloging source in 040 $a (Original cataloging agency) is responsible for the data content of the record. The organizations identified as the transcribing agency in field 040 subfield $c (Transcribing agency) is responsible for the tagging and transcription of the data.

In modified records, organizations identified in field 040 $a (Original cataloging agency) and $d (Modifying agency) are collectively responsible for the data content of the record. Organizations identified as transcribing or modifying agencies in field 040 $c and $d are collectively responsible for the tagging and transcription of the data.

An agency-assigned data element is one whose content is determined by a designated agency and is the responsibility of that agency, e.g., field 222 (Key Title) which is the responsibility of an ISSN Center. While it is usually input by the designated agency, it may be transcribed by another organization.

Certain data elements contain data from controlled lists maintained by designated agencies, e.g., the MARC Code List for Languages in field 041 (Language Code) of the bibliographic format. These elements are indicated at the field or subfield level in MARC 21 and only values from the designated lists may be used. If a change or addition is desirable for a list, the maintenance agency for the list should be consulted.

Multiscript Records

A MARC 21 record may contain data in multiple scripts. One script may be considered the primary script of the data content of the record, even though other scripts are also used for data content. (Note: ASCII is used for the structure elements of the record, with most coded data also specified within the ASCII range of characters.) Examples and models for multiscript data are described in the Multiscript Records section.


Content Designators not in this Document

Many valid MARC 21 tags, subfield codes and values are not included in this document. They may be found in the online MARC 21 Concise Bibliographic Format. Any valid tag may be used in a MARC 21 LITE Record. Obsolete content designators are not included in this document.

In the Summary Statement of Content Designators section, all MARC 21 fields not identified for inclusion in MARC 21 LITE are listed with links to their descriptions in the MARC 21 Concise Bibliographic Format. At each field included in this document is a link to the same field in the MARC 21 Concise Bibliographic Format where values or subfields are described that are not identified for inclusion in the MARC 21 LITE Bibliographic Format.

An obsolete content designator is not used in new records. It may appear in records that were created prior to the time that it was made obsolete.

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 distinguised 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).

Standards Used

International and National Standards

ISO 2108: International Standard Book Numbering (ISBN) (ANSI/NISO Z39.21)

ISO 3901:International Standard Recording Code (ISRC)

ISO 3297: International Standard Serial Number (ISSN) (ANSI/NISO Z39.9 )

ISO 10324: Holdings Statements - Summary Level (ANSI/NISO Z39.71)

MARC Code Lists

MARC Code List for Countries

MARC Code List for Geographic Areas

MARC Code List for Languages

MARC Code List for Organizations

MARC Code Lists for Relators, Sources, Description Conventions


This 2006 edition of the MARC 21 LITE Bibliographic Format includes the base text (February 1999), along with Update No. 1 (October 2000), Update No. 2 (October 2001), Update No. 3 (October 2002), Update No. 4 (October 2003), Update No. 5 (October 2004), Update No. 6 (October 2005), Update No. 7 (October 2006) and Update No. 8 (October 2007) of the MARC 21 Format for Bibliographic Data.

The MARC 21 LITE Bibliographic Format is prepared by the Network Development and MARC Standards Office. Direct any questions related to the content of this document to the Library of Congress, Network Development and MARC Standards Office, 101 Independence Ave., S.E., Washington, DC 20540-4402 (FAX +1-202-707-0115). Correspondence may also be sent to the office email account at:

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