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Genealogy Classification System

Genealogy Classification System

Jump to: Quick Reference, Overview, Category Codes, Content Codes, US State Codes, Numeric Topic Designators, Acknowledgements.

Overview

The classification system used to organize the materials in the WDH Carolina Research Center is different from the Dewey Decimals used in the rest of the PCPL system. It is primarily geographical, but it isn't limited to just geographical information. Since it is so different, it takes a bit of use to grow comfortable with it. There's a poster of the system in the building for quick reference, and you can also jump to an on-line quick reference.

For a full in-depth discussion, read below.

The classification starts with a two-letter code assigning material to a broad category. The most common categories are US states, represented by two-letter postal codes. Other categories cover non-geographically specific topics. They are: general information (especially on genealogy resources and how-to); biographies; church histories; historic preservation; Ethnic and Emigration/Imigration; Family Histories; Genealogies not specific to a US state; History; a Miscelaneous category, for what ever doesn't fit anywhere else.

Next comes a three-letter code decribing the content of the material. Again, most common is a geographical reference: a three-letter abbreviation for a county within a US state. Other codes are used for non-geographically-specific materials, or materials which refer to more than one county.

The next level of classification is a numeric designator used to specify the topic of material. These numeric designators are used with all of the category and content (two and three letter) codes, and mean the same thing regardless of which category/content they're used with. For example, the designator ".3" always means public records, whether in genealogy, biography, history, or whatever.

After category, content, and topic comes a three-letter abbreviation of the last name of the author, editor, or compiler of the material.

Top Level Categories (Two-Letter)

Materials are divided into categories using a two-letter code.

  • Materials relating to a particular US state or territory use the two-letter US Postal Service code: NC for North Carolina, AK for Alaska, and so on. The complete list is maintained by the USPS. The classification is very US centric, and states/provinces of other nations are not used.
  • For materials which aren't geographically focused, or which don't fall neatly into one US state, there are two-letter codes starting with "A" chosen so they don't conflict with USPS codes.
The non-state categories are:
  • AA General information, indexes, how-to (especially Genealogy), bibliographies, and more.
  • AB Individual biographies, followed by the name of the subject. A biography of Andrew Jackson by Frederic Bass would be classified as "AB Jackson BAS".
  • AC Church histories — national or wider geographically. The numeric designator can indicate denomination (See .5)
  • AD Historic preservation, documents, buildings and artifacts, oral history.
  • AE Ethnic [particularly Native Americans] and immigration/emigration materials. The numeric designator can specify ethic or religious group (See. .5, .6)
  • AF Family Histories followed by surname of family per LCSH. A family history of the Smith family, compiled by Fred Jones would be classified as "AF Smith JON".
  • AG Genealogies not specific to any one US state or territory.
  • AH General History.
  • AJ Miscellany: whatever doesn't fall into any of the other top-level categories.

Each of these will be modified by content (three letter) code and topic numeric designator to help make the classification very specific to a geographic location (or other content) and topic within the category. Note that the content code and topic designator always mean the same thing, regardless of which top level category they apply to.

The two exceptions to the "category - content - topic" classification format are the biographies and family histories, as mentioned in the table above.

  • Biography classifications start with "AB". Next comes the full last name of the subject. ABs end with the first three letters of the biographer's last name
  • Bascially all books which contain a family name in the title are assumed to be Family History, and start with "AF". Next comes the full family name. Note that many AF books contain info about more than one family, or may have more than one family name in the title. In those cases we try to figure which family is the primary topic, or earliest in the family tree. If all else fails, we use the first family in the title. AF classifications end with the first three letters of the Authors, editors, or compilors last name.

Content (Three-Letter) Classifications

The Content classifications are assigned three-letter codes which can be geographical or topical.

  • The most common geographical codes are for counties or cities when the top-level (two-letter) specifies a US state or territory. These codes are usually the first 3 letters of the county. If the first three letters of two or more county names are the same, the alphabetically second county will receive a different abbreviation. Some cities (especially in Virginia) are not considered part of any county. They are assigned abbreviations from the ARRL 3-letter Virginia Independent City Abbreviation list.
  • If the top-level is non-geographical, the second level may specify a continent (AFR, ANT, ASI, AUS, EUR, NOA, SOA), or may use the three-letter international country codes.
  • There are a small number of non-geographical second level codes:

    • BIB Bibliographies
    • DIC Dictionaries
    • DIR Directories
    • HER Heraldry and name dictionaries
    • IND Indexes
    • INS Instructional
    • AAA Everything else genealogical
    • ZZZ Everything else not genealogical

    Of these, only IND is currently also a country code (India). It should be pretty clear from the category and/or topic which content is intended.

    AAA and ZZZ deserve further clarification:

    • AAA is for genealogical information which can't be assigned one of the other content codes. It's used most often when the material applies to more than one county (or all counties) within a state, or to more than one country. It's assumed the topic numeric designator will give more detail.
    • ZZZ is used for everything not either genealogical or geographically specific. The topic numeric designator does the work of showing what the material is about.

    Topic Designator

    Topic designators specify what information the material holds. Topic designators always have the same meanings across all categories and content. They are appended to the content code with a period ("."). The first digit after the period indicates a broader area, and the second digit specifies more completly within that area. In rare cases a third digit may be required or used for clarity.

    • .1 general information.
      • .1 charts of data
      • .12 directories
      • .13 how to
      • .14 bibliographies
      • .15 immigration/ emigration
      • .16 Indexes
      • .17 sources, i.e. guides to holdings
      • .18 [not used]
      • .19 gazetteers, atlases, and maps

    • .2 Compilations, society, and arts and sciences
      • .2 collective biography
      • .21 heraldry and name dictionaries
      • .22 compiled genealogies, including by regions, countries, and continents
      • .23 travel, description, and geography
      • .24 education, training, and apprenticeships
      • .25 commerce and labor
      • .26 culture and social life
      • .27 arts and sciences:
        • .271 philosophy and psychology
        • .272 religion
        • .273 social sciences
        • .274 languages
        • .275 natural sciences and math
        • .276 technology and applied science
        • .277 fine and decorative arts
        • .278 literature
      • .28 law and legislation; politics and government
      • .29 architecture

    • .3 Public Records
      • .3 censuses, date comes before author designation
      • .31 vital statistics, combined records, i.e. death and birth records
      • .32 Bible records
      • .33 court records
      • .34 marriage, divorce, and cohabitation records
      • .35 cemetery records
      • .36 wills and estate records/probate
      • .37 deeds and land records
      • .38 tax records and voter registrations
      • .39 newspaper abstracts, obituaries, etc.

    • .4 military records and pension lists. A "1" may be appended to indicate a time between two wars. This should only be used with military records.
      • .41 pre—discovery wars
      • .42 Colonial wars
      • .43 Revolutionary War
      • .44 War of 1812
      • .45 Mexican War [4/1846—2/1848]
      • .46 Civil War
      • .461 Reconstruction
      • .47 Spanish—American War [1898]
      • .48 World War I
      • .49 World War II
      • .491 late 20th century

    • .5 Church records and histories
        .5 non-denominal or inter-denominal
      • .51 Baptist
      • .52 Catholic
      • .53 Quaker
      • .54 Episcopal
      • .55 Lutheran
      • .551 Reformed, Church of Christ
      • .56 Methodist
      • .57 Moravian, Mennonite, Amish
      • .58 Presbyterian
      • .59 Other denominations

    • .6 Ethnicity
      • .6 Ethnic records, general information about ethnic character of the United States
      • .61 Celtic/Gaelic, e.g. Scots, Welsh, Breton
      • .62 English, Anglo—Saxon
      • .63 Teutonic, Germanic, Scandinavian
      • .64 Baltic/Slavic
      • .65 Latin/Romance countries, e.g. Italian, French, Spanish
      • .66 African—American
      • .67 American Indian
      • .68 Semitic
      • .69 other, e.g. Melungeons

    • .7 History
        .7 county and area histories
      • .71 Heritage books
      • .72 Eastern standard zone, north
      • .73 Eastern standard zone, south
      • .74 central standard zone, north
      • .75 central standard zone, south
      • .76 mountain standard zone, north
      • .77 mountain standard zone, south
      • .78 Pacific standard zone, north
      • .79 Pacific standard zone, south

    • .8 preservation
      • .81 historiography
      • .82 oral history
      • .83 documents
      • .84 photographs
      • .85 buildings

    • .9 periodicals
    • .91 genealogical and other society records
    • .92 community development

    Quick Reference

    The general form of the classification is a two-letter category code, three-letter content code, the topic 2 or 3 digit numerical designator, and the first three letters of the last name of the author, editor, or compiler. Three exceptions:

    • Biography: "AB subject_last_name AUT"
    • Family History: "AF family_name AUT"
    • US Census includes year: "AG USA.3 1790 AUT"

    Two-letter codes may be either the USPS state/territory code, or one of:

    • AA General information, indexes, how-to (especially Genealogy), bibliographies, and more.
    • AB Individual biographies
    • AC Church histories
    • AD Historic preservation, documents, buildings and artifacts, oral history
    • AE Ethnic [particularly Native Americans] and immigration/emigration materials.
    • AF Family Histories followed by surname of family per LCSH.
    • AG Genealogies not specific to any US state or territory.
    • AH General History.
    • AJ Miscellany: whatever doesn't fall into any of the other top-level categories.

    Three-letter codes are either geographical (county, country, continent) or one of:

    • BIB Bibliographies
    • DIC Dictionaries
    • DIR Directories
    • IND Indexes
    • INS Instructional
    • HER Heraldry and name dictionaries
    • AAA Everything else genealogical
    • ZZZ Everything else not genealogical

    Numeric designator. Jump to: .1 General; .2 Compilation; .3 Public; .4 Military; .5 Church; .6 Ethnic; .7 History; .8 Preservation; .9 Periodicals.

    • .1 general information.
      • .1 charts of data
      • .12 directories
      • .13 how to
      • .14 bibliographies
      • .15 immigration/ emigration
      • .16 Indexes
      • .17 sources, i.e. guides to holdings
      • .18 [not used]
      • .19 gazetteers, atlases, and maps

    • .2 Compilations, society, and arts and sciences
      • .2 collective biography
      • .21 heraldry and name dictionaries
      • .22 compiled genealogies, including by regions, countries, and continents
      • .23 travel, description, and geography
      • .24 education, training, and apprenticeships
      • .25 commerce and labor
      • .26 culture and social life
      • .27 arts and sciences.
      • .28 law and legislation; politics and government
      • .29 architecture

    • .3 Public Records
      • .3 censuses, date comes before author designation
      • .31 vital statistics, combined records, i.e. death and birth records
      • .32 Bible records
      • .33 court records
      • .34 marriage, divorce, and cohabitation records
      • .35 cemetery records
      • .36 wills and estate records/probate
      • .37 deeds and land records
      • .38 tax records and voter registrations
      • .39 newspaper abstracts, obituaries, etc.

    • .4 military records and pension lists.
      • .41 pre—discovery wars
      • .42 Colonial wars
      • .43 Revolutionary War
      • .44 War of 1812
      • .45 Mexican War
      • .46 Civil War
      • .461 Reconstruction
      • .47 Spanish—American War
      • .48 World War I
      • .49 World War II
      • .491 late 20th century

    • .5 Church records and histories
        .5 non-denominal or inter-denominal
      • .51 Baptist
      • .52 Catholic
      • .53 Quaker
      • .54 Episcopal
      • .55 Lutheran
      • .551 Reformed, Church of Christ
      • .56 Methodist
      • .57 Moravian, Mennonite, Amish
      • .58 Presbyterian
      • .59 Other denominations

    • .6 Ethnicity
      • .6 Ethnic records, general information about ethnic character of the United States
      • .61 Celtic/Gaelic
      • .62 English, Anglo—Saxon
      • .63 Teutonic, Germanic, Scandinavian
      • .64 Baltic/Slavic
      • .65 Latin/Romance countries
      • .66 African—American
      • .67 American Indian
      • .68 Semitic
      • .69 other

    • .7 History
        .7 county and area histories
      • .71 Heritage books
      • .72 EST, north
      • .73 EST, south
      • .74 CST, north
      • .75 CST, south
      • .76 MST, north
      • .77 MST, south
      • .78 PST, north
      • .79 PST, south

    • .8 Preservation
      • .81 historiography
      • .82 oral history
      • .83 documents
      • .84 photographs
      • .85 buildings

    • .9 Periodicals
    • .91 genealogical and other society records
    • .92 community development

    Origin of the Classification System

    PCPL adapted this classification system from the Rowan County Public Library system, who in turned adapted it from Arlington, TX public libraries. Many thanks to them for creating a classification well suited to genealogical and local history. The original (scholarly) paper describing the creation of the sytem may be read here (1 MB PDF file): Arranging Roots: Classification and Subject Headings for Genealogical Collections.