Information:
In order to access information in a collection,
library users can search by different subjects that
describe in a word or a phrase the contents of a
particular item. If library users want books about
cats they could look under the subject "Cats". This
makes the collection more accessible because the
library users would not have to know the title or
the author of individual items to locate the
information they need.
In the MARC bibliographic record there are several
tags which represent different types of subject
headings. The 650 tag provides topical or general
subject headings, phrase subject headings including
general names of meetings, events, or objects, and
phrase topics that begin with a geographic name.
This subject heading would NOT include personal
names of real people, specific meetings and events,
corporate bodies, or geographic places.
Subject headings are derived from a controlled
vocabulary list such as Sears List of Subject
Headings or Library of Congress Subject
Headings. Not using a controlled vocabulary
list of subject heading terms can cause confusion
and frustration for library searchers. For example,
in an uncontrolled vocabulary, a library searcher
looking for information about the abuse of drugs
might look under such subjects as: "Abuse of
drugs", "Drug habit", "Drug misuse", "Drug use",
"Drug abuse", or any number of other phrases or
terms. However, if the library uses controlled
subject heading terms, all of the material about
the abuse of drugs should be given the same subject
heading from the controlled subject heading list
and cross references would lead the library user to
the correct term.
The addition of subdivision terms to the subject
headings also provides more precise subject access.
The subdivisions and the rules for using them are
established by the agency responsible for the
subject heading system.
In the 650 tag the second indicator tells which
authorized subject heading list is used. When using
Sears headings, enter 7 as the second indicator and
sears (all lower case letters) in subfield 2.
Indicators
First Level of subject
blank No information provided
Second Subject heading system/thesaurus
0 Library of Congress Subject Headings
1 LC subject headings for children's
literature
2 Medical Subject Headings
3 National Agricultural Library subject
authority file
4 Source not specified
5 Canadian Subject Headings
6 Répertoire des vedettes-matière
7 Source specified in subfield 2
Subfields
a Topical term or geographic name as entry
element (NR)
v Form subdivision (R)
x General subdivision (R)
y Chronological subdivision (R)
z Geographic subdivision (R)
2 Source of heading or term (NR)
Punctuation
This tag ends with a mark of punctuation
(., !, ?, -) or a closing parenthesis. This mark of
punctuation precedes subfield 2 when present.
Examples:
Library of Congress Subject Headings (LCSH)
and LC's Name Authority List are designed for LC's
own collection and are used by many large public
libraries, college and university libraries, and
special libraries. LC's lists are comprehensive,
and have a large number of free-floating
subdivisions that can be added to names.
650 0 _aAdventure and adventurers
_zUtah
_vFiction.
650 0 _aAdvertising
_vNewspapers.
650 0 _aCanada goose.
650 0 _aChildren's parties.
650 0 _aComputer industry.
650 0 _aCooking (Bananas)
650 0 _aEnglish language
_xOrthography and spelling.
650 0 _aFrontier and pioneer life
_zMontana.
650 0 _aHeroes.
650 0 _aWomen heroes.
650 0 _aHistory, Modern
_y19th century.
650 0 _aImaginary companions.
650 0 _aMythology, Classical.
650 0 _aRoads
_xDesign and construction
_xEquipment and supplies.
650 0 _aScience and civilization
_y20th century.
650 0 _aSevere storms
_zOklahoma.
650 0 _aSwine
_zIowa.
Library of Congress Subject Headings for Children's
Literature or Annotated Card (AC) Headings
generally use LCSH terms; however, sometimes it
substitutes a more familiar or shortened version of
the subject in the AC heading.
650 1 _aAdventure and adventurers
_vFiction.
650 1 _aCookery
_xBananas.
650 1 _aEnglish language
_xSpelling.
650 1 _aFrontier and pioneer life
_zMontana.
650 1 _aImaginery playmates
_vFiction.
650 1 _aParties.
650 1 _aPigs.
Sears List of Subject Headings is designed
to meet the needs of small and medium-sized
libraries. Sears provides a smaller, more
simplified list of subjects and subdivisions to use
than LCSH. Sears also allows for narrower headings
being added by the library under certain specified
categories.
650 7 _aAdventure fiction.
_2sears
650 7 _aAdvertising
_vNewspapers.
_2sears
650 7 _aCanada geese.
_2sears
650 7 _aChildren's parties.
_2sears
650 7 _aClassical mythology.
_2sears
650 7 _aComputer industry.
_2sears
650 7 _aCooking
_xBananas.
_2sears
650 7 _aEnglish language
_xSpelling.
_2sears
650 7 _aFrontier and pioneer life
_zMontana.
_2sears
650 7 _aHeroes and heroines.
_2sears
650 7 _aImaginery playmates
_vFiction.
_2sears
650 7 _aWorld history
_y19th century
_2sears
650 7 _aParties.
_2sears
650 7 _aPigs.
_2sears
650 7 _aRoads
_xDesign and construction
_xEquipment and supplies.
_2sears
650 7 _aScience and civilization.
_2sears
650 7 _aStorms.
_2sears
|