1 Introduction

Chapter overview

This chapter outlines the databases and interfaces available within the OCLC® online system, and describes the makeup of the OCLC and Library of Congress authority files.

1.1 OCLC Online System

The OCLC® Online System provides the following library support systems:

Cataloging—for cataloging materials and producing catalog cards, machine-readable records and other products.
Interlibrary Loan—for borrowing and lending materials.
Union List—for creating, maintaining and displaying summary-level holdings information.

You can access the following databases:

The WorldCat®database—a database of bibliographic records and institution-level holdings information.
The OCLC Authority File—a database of authority records for name and subject headings and other authority information.
The Policies Directory—a database of names, addresses, and other information about vendors, publishers, libraries and other organizations and groups associated with publishing and libraries.

System access

You access these databases through the following interfaces:

OCLC Connexion^TM browser
OCLC Connexion^TM client
OCLC Cataloging Micro Enhancer® (CatME)
OCLC Passport for Windows software (Passport)

For system requirements and installation details, see the documentation for the specific OCLC interface your library uses.

For instructions to access the OCLC Authority File, see chapter 2, Accessing the OCLC Authority File.

1.2 OCLC Authority File

Definition

An authority record is a collection of information about one name, uniform title or topical term heading. You search authority records in the OCLC Authority File to determine if an authoritative heading exists. If the heading exists, it provides you with the established form of the heading, see from references, see also from references and notes.

The OCLC Authority File allows you to display, create and maintain authoritative headings in authority records as part of the cataloging, reference or acquisitions process.

Types of headings

The OCLC Authority File contains the following types of headings:

Personal names
Corporate names
Conference names
Geographic names
Uniform titles
Series titles
Subject headings (topical terms as well as names and uniform titles with subject subdivisions)
Children's subjects
Subdivision headings

Library of Congress and NACO

The Library of Congress (LC) and the Program for Cooperative Cataloging (PCC) authorities component (NACO) participants create and contribute authority records according to specifications in MARC 21 Format for Authority Data (Library of Congress, 1999 base text) and Update No 1. (Library of Congress, October 2000) or other LC manuals.

The information in authority records is based on:

Anglo-American Cataloguing Rules (AACR1 and AACR2)
Library of Congress Rule Interpretations (Library of Congress, 2nd edition, 1989- )
Subject Cataloging Manual: Subject Headings (Library of Congress, 24th edition, 2001)

LC record loads

OCLC adds records created by LC and NACO through electronic transfer (File Transfer Protocol—FTP). OCLC adds name and uniform title authority records daily and subject authority records weekly.

1.3 Library of Congress Authority Files

The OCLC Authority File contains records received from the Library of Congress (LC). LC maintains two separate authority files: one for names and one for subjects.

LC name authority file

LC and NACO participants create headings for personal, corporate, conference and geographic names. Uniform title and series headings are also included in the name authority file.

LC subject authority file

LC creates records for headings and heading-subdivision combinations that they plan to include in Library of Congress Subject Headings (LCSH). LC does not create a record for every unique heading-subdivision combination assigned to a bibliographic record.

Categories not printed in LCSH. Because LCSH excludes the following categories of headings for printing in LCSH, LC creates no subject authority records for:

Names of persons, unless used as a pattern or example, or unless a subdivision must be printed.
Names of corporate bodies and jurisdictions, unless used as a pattern or example, or unless a subdivision must be printed.
Headings incorporating free-floating subdivisions, unless needed for use as a reference to another heading, or followed by a non free-floating subdivision.
Phrase headings created by incorporating free-floating terms (e.g., . . . Region, . . . Valley, . . . in art, . . . in literature).

LC creates and distributes name authority records for the first two categories. Passport Help contains pattern headings for the first two categories. OCLC Connexion browser Help lists pattern headings for topical subjects.

Excluded records. The subject authority file excludes records for non-LC authority systems such as MeSH (Medical Subject Headings), NAL (National Agricultural Library) and NLC (National Library of Canada).

LC authority record prefixes

LC assigns authority record control numbers (LCCNs) to all authority records. The control number consists of an alphabetic prefix plus eight digits. The alphabetic prefix indicates which system created the authority record.

System	Assigned Prefix(es)
LC	n for name headings sh for subject headings sj for subject headings for children
OCLC	no
RLG (Research Libraries Group)	nr
British Library	nb

Unique characteristics in LC records

LC subject records may contain the following unique characteristics:

The coding of the fixed field may not clearly indicate whether a subject heading can be divided geographically.
Source data information (e.g., 670 fields) may not be present in all existing authority records. However, newly created records carry source data.
Coding in the 4xx and 5xx fields for related and broader terms is based on the reference structure at the time of LC's internal file conversion. However, the coding of some broader or related term references may require reconsideration on a case-by-case basis. LC subject-authority records do not carry narrower term references.

Formerly used cross-references

The LC Authority File contains only headings and cross-references from the current edition of LCSH, its supplements, and weekly lists. Cross-references needed to link subject headings formerly used (and still found in older OCLC records) to the form now used may or may not be present.

Geographic subdivision practice

When you see the fixed field element label INDIRECT or DIRECT in a mnemonic authority record display, the heading in field 150 may undergo subdivision by place.

The label NOT SUBD GEOG means that the heading in field 150 may not be subdivided geographically. Tagged displays convey the same information by codes i, d, or blank in Geo subd.

LC uses a fill character, , in Geo subd to indicate that the heading in field 150 may not be subdivided geographically and that there has been no effort to code the data. In this case, the system supplies no label to indicate geographic subdivision practice in a mnemonic display. Check the main topical heading to determine appropriate geographic subdivision practice.

More information. See section C.2, "Fixed Field Mnemonic Labels," of appendix C, OCLC Authority Record Format for more information about the labels used in the mnemonic display.

1.4 OCLC Authority Records

Like a bibliographic record, an OCLC authority record contains a fixed field element area and a variable field area. Although the content is uniform among the interfaces, placement of the areas is not. The name authority record for Arawata, Bill is shown here as it appears in each interface.