Content Designators

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Content Designators

Content designators include those "signposts" which guide the computer in interpreting the information found in a cataloging record. These "signposts" include the field, tag, indicator, subfield, and subfield code(s).

A field is a seperately designated part of an encoded record which may contain one or more subfields (1). For example, fields are included for author, title, Library of Congress Control Number, International Standard Book Number, and physical description, to name but a few. When we see such lengthy fields as Library of Congress Control Number, we understand that it would be implausible to include these verbatim into the MARC record. Instead, each field is represented by a 3-digit "tag."

A tag is a 3-digit representation of a field and identifies what information relevant to that field is forthcoming. For example, the tag 010 indicates that what follows is the Library of Congress Control Number (LCCN); the tag 300 indicates a proceeding physical description. In the MARC record 90% of all applicable tags are rarely used. The remaining 10% become increasingly familiar with repetition. What follows is a partial listing of the more commonly used tags:

010 - Library of Congress Control Number(NR)

020 - International Standard Book Number(R)

100 - Main entry - Personal name(NR)

130 - Title statement(NR)

250 - Edition statement(NR)

260 - Publication, distribution, etc.(NR)

300 - Physical description(R)

600 - Subject added entry - Personal name(R)

650 - Subject added entry - Topical term(R)

You may have noticed the acronyms (R) and (NR). These stand for Repeatable and Non-Repeatable and are explained thusly: if a tag can appear more than once in a bibliographic record, it is designated with an (R); if it cannot appear more than once, it is thereby designated with an (NR).

Immediately following a tag is an indicator. There are two indicators assigned to two seperate character positions. Although the use of letters to indicate the value of a character position is not forbidden, thay are usually represented by numbers 0-9. When discussing indicators it is extremely important to remember that each digit (of the two) is an entity of and within itself. It is not uncommon for either digit to be undefined; if this is indeed the case, the character # is usually given in its stead. In this scenario # is understood to connote "blank space."

What follows the indicator(s) is a record's subfield (except in fields 001-009). The subfield of a record is marked by subfield codes and delimiters. When reviewing a MARC record it is not uncommon to see more than one subfield; in fact this is expected, because any data seperated within a field is considered a subfield. Each subfield is usually preceded by a lowercase letter, which is the subfield code spoken of earlier. This code is itself preceded by a delimiter, usually in the form of $. Subfields can include several pieces of data for one particular field. Subfield codes are used to identify elements included in a field which may require seperate manipulation; these codes are defined seperately for each field. In the field "tagged" 260 (Publication, distribution, etc.), subfields one might expect to see are:

$a - Place of publication, distribution, etc.

$b - Name of publisher, distributor, etc.

$c - Date of publication, distribution, etc.

There are other delimiters one may see from time to time, including @, and _.

It is important to note that, due to ongoing revisions, content designators may be added, made obsolete, or even deleted from various formats. When a data element is no longer needed, or a particular designation is considered no longer applicable, it is made obsolete. A deleted content designator is reserved in MARC 21, but is either undefined or has not been previously used (5).

Here is an example inclusive of information given on this page:

245 10 $a Steppenwolf $c Translated form the German by Basil Creighton (allowances are made for clarity)

245 - Field - Title statement (NR)

1 - Title added entry

0 - Nonfiling characters (number of non-filing characters present, including spaces, which dictates the number of spaces allowable before the official title entry begins. For example, if the title begins with The Man, there will usually be a 4 in this place. This means that the letters T, h,and e, and the space following them are ignored, so that the title proper will be filed under the less redundant Man.

$ - Delimiter

$a - Subfield - The title proper

$ - Delimiter

$c - Subfield - Remainder of the title page transcription/Statement of responsibility

This concludes the section on content designation.


	Playing With MARC \| home A Brief History \| The Machine-Readable Cataloging Record \| Content Designators \| Field Tag Formulas \| The Necessity of Standards \| Bibliography Content Designators Content designators include those "signposts" which guide the computer in interpreting the information found in a cataloging record. These "signposts" include the field, tag, indicator, subfield, and subfield code(s). A field is a seperately designated part of an encoded record which may contain one or more subfields (1). For example, fields are included for author, title, Library of Congress Control Number, International Standard Book Number, and physical description, to name but a few. When we see such lengthy fields as Library of Congress Control Number, we understand that it would be implausible to include these verbatim into the MARC record. Instead, each field is represented by a 3-digit "tag." A tag is a 3-digit representation of a field and identifies what information relevant to that field is forthcoming. For example, the tag 010 indicates that what follows is the Library of Congress Control Number (LCCN); the tag 300 indicates a proceeding physical description. In the MARC record 90% of all applicable tags are rarely used. The remaining 10% become increasingly familiar with repetition. What follows is a partial listing of the more commonly used tags: 010 - Library of Congress Control Number(NR) 020 - International Standard Book Number(R) 100 - Main entry - Personal name(NR) 130 - Title statement(NR) 250 - Edition statement(NR) 260 - Publication, distribution, etc.(NR) 300 - Physical description(R) 600 - Subject added entry - Personal name(R) 650 - Subject added entry - Topical term(R) You may have noticed the acronyms (R) and (NR). These stand for Repeatable and Non-Repeatable and are explained thusly: if a tag can appear more than once in a bibliographic record, it is designated with an (R); if it cannot appear more than once, it is thereby designated with an (NR). Immediately following a tag is an indicator. There are two indicators assigned to two seperate character positions. Although the use of letters to indicate the value of a character position is not forbidden, thay are usually represented by numbers 0-9. When discussing indicators it is extremely important to remember that each digit (of the two) is an entity of and within itself. It is not uncommon for either digit to be undefined; if this is indeed the case, the character # is usually given in its stead. In this scenario # is understood to connote "blank space." What follows the indicator(s) is a record's subfield (except in fields 001-009). The subfield of a record is marked by subfield codes and delimiters. When reviewing a MARC record it is not uncommon to see more than one subfield; in fact this is expected, because any data seperated within a field is considered a subfield. Each subfield is usually preceded by a lowercase letter, which is the subfield code spoken of earlier. This code is itself preceded by a delimiter, usually in the form of $. Subfields can include several pieces of data for one particular field. Subfield codes are used to identify elements included in a field which may require seperate manipulation; these codes are defined seperately for each field. In the field "tagged" 260 (Publication, distribution, etc.), subfields one might expect to see are: $a - Place of publication, distribution, etc. $b - Name of publisher, distributor, etc. $c - Date of publication, distribution, etc. There are other delimiters one may see from time to time, including @, and _. It is important to note that, due to ongoing revisions, content designators may be added, made obsolete, or even deleted from various formats. When a data element is no longer needed, or a particular designation is considered no longer applicable, it is made obsolete. A deleted content designator is reserved in MARC 21, but is either undefined or has not been previously used (5). Here is an example inclusive of information given on this page: 245 10 $a Steppenwolf $c Translated form the German by Basil Creighton (allowances are made for clarity) 245 - Field - Title statement (NR) 1 - Title added entry 0 - Nonfiling characters (number of non-filing characters present, including spaces, which dictates the number of spaces allowable before the official title entry begins. For example, if the title begins with The Man, there will usually be a 4 in this place. This means that the letters T, h,and e, and the space following them are ignored, so that the title proper will be filed under the less redundant Man. $ - Delimiter $a - Subfield - The title proper $ - Delimiter $c - Subfield - Remainder of the title page transcription/Statement of responsibility This concludes the section on content designation.