Version 4

    Archival Dictionary



    The National Archives in Washington, DC, known as Archives I



    The National Archives at College Park, Maryland, known as Archives II


    Access Restriction

    Lets the researchers know if they are allowed to request the records. There are 4 categories of access:

    • Unrestricted – Free for anyone to request and see; the majority of our records are unrestricted.
    • Restricted – Possibly – Records may be requested, but someone must screen them before signing them out to a researcher.

           See "Screening" below for a definition of this process.

    • Restricted – Partly – Some of the documents or boxes may have an access restriction on them. This can range from

           a withdrawn document to a range of boxes that are not available for researchers.

    • Restricted – Fully – These records are 100% restricted from being seen by researchers.


    Some common access restriction reasons:

    • FOIA b(1) - National Security
    • FOIA b(3) - Statute - can include Grand Jury information, statutes on Arms Control, and the Atomic Energy Act
    • FOIA b(6) - Personal Privacy - can include Social Security numbers, medical information
    • FOIA b(7) - Law Enforcement Information - typically found in Secret Service and FBI records


    Accession Number

    This is a number that tells when the National Archives received the records. The first set of numbers tells the record group (RG)

    that the records were transferred as. The second number set tells what year the National Archives received the records.

    The third set of numbers tells where in the year a set of records were received.


    So for the accession number NN3-059-95-026


    059 is for Record Group 59, General Records of the Department of State

    95 is for 1995 - when the records were received

    026 - this was the 26th accession for 1995



    A collection of historical documents or records providing information about a place, institution, or group of people. 

    (Our definition: It's all the cool stuff we are holding for you in our buildings).



    Process used to establish physical and intellectual control over records and the organization and sequence of items within a collection.


    Box List

    This is a list of the first and last folder in each box. Not all series will have this.



    The National Archives uses this term typically to denote groups of materials donated by individuals.



    Who maintained the series before it was transferred to the National Archives. This is not necessarily the same as who created the records.

    The Creator is who the records lived with before getting to us at NARA.


    A creator is written to show the hierarchy of an organization. The first organization in a creator is the highest level, and it works its way down to the lowest level office that maintained the records.


    Example: Department of Justice. Office of the Deputy Attorney General.


    Declassification Project Number

    This is a NARA-assigned identifier that says the records have gone through the Declassification Review process.

    This does not necessarily mean all of the records have been declassified, only that they have been reviewed by our staff.


    See Access Restriction for more information on records that may still be restricted after going through the Declassification Review. 


    Entry Number

    This is the unique identifier given to series when they are processed to differentiate the series from other series in a group of records.


    File Unit

    A folder of records. Some of these will be listed in the Catalog, but many will not be.


    This is the third level of archival arrangement. From the largest grouping to an individual document the levels go like this:

    Record Group, Series, File Unit, Item/Asset (the individual document or image).



    This stands for Freedom of Information Act.  It is a freedom of information law that allows for full or partial release of previously unreleased materials controlled by the Federal government.


    Folder List

    A list of every folder in the boxes in a series. If a series has a folder list in the catalog, it will be listed as file units.


    HMS/MLR Entry Number

    MLR is the old version of NARA’s staff-only catalog. The current version, HMS stands for Holdings Management System.


    This number can help an archivist in reference find the series you are looking for. This is also a number that will be on the boxes, so try to remember to write it down on your pull slips!



    Stands for the National Archives Catalog where researchers can search for records. It can be found here:

    Commonly referred to as “the Catalog”



    That’s us! The National Archives and Records Administration - check us out at


    NAID/ARC Identifier

    The unique and stable identifier all series in the Catalog use. NAID stands for National Archives IDentifier.

    ARC is the predecessor to the Catalog.


    Some box labels will have this number on it, but most will not.


    NPRC - National Personnel Records Center

    This is where personnel files of former civilian Federal employees live. It is also where all official Military Personnel Files live.

    You cannot research in person here, but you can submit a request for your military records here:


    Original Order

    A fundamental principle of archives; the organization and sequence of records established by the creator of the records.  Whenever possible, records should be left in the original order.



    Activities which prolong the usable life of archival records. Preservation activities are designed to minimize the physical and chemical deterioration of records and to prevent the loss of informational content.



    This principle provides that records be attributed to the agency that created or maintained them and arranged thereunder as they were filed when in active use.


    Record Group (RG) and Record Group Number

    A grouping of records based on a high-level organization. These are like big buckets that we put series into to group them together. You can search for a record group either here, in the Guide to Federal Records in the National Archives: or in the National Archives Catalog:


    This is the highest level of archival arrangement. From the largest grouping to an individual document the levels go like this:

    Record Group, Series, File Unit, Item/Asset.


    Some examples:

    RG 48 - Records of the Office of the Secretary of the Interior

    RG 59 - General Records of the Department of State

    RG 120 - Records of the American Expeditionary Forces (World War I)


    Scope & Content

    A basic description of what the records contain. It might include things like types of records (correspondence, memos, photographs), and topics covered (international treaties, troop movements). It might also include mentions of records in languages other than English.



    The process of reviewing the records to ensure they do not contain sensitive information that should not be made public.

    Such records might include Social Security numbers, medical information, or proprietary business information.



    A smaller grouping of records inside a record group. This could be because of a topic, purpose, or division inside an agency.


    This is the second level of archival arrangement. From largest grouping to an individual document the levels go like this:

    Record Group, Series, File Unit, Item/Asset.


    Use Restriction

    These are restrictions on how you can use the records in your own work. Use restrictions do not prevent you from seeing the records.

    The most common use restriction is Copyright.