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MODS User Guidelines (ver. 3) Home » Top-level Elements and Attributes » Top-level Element:<physicalDescription>

Top-level Element: <physicalDescription>

Element <physicalDescription>
Definition Describes the physical attributes of the information resource.
Attributes displayLabel; altRepGroup; lang; xml:lang; script; transliteration; unit
Subelements <form> <reformattingQuality> <internetMediaType> <extent> <digitalOrigin> <note>

GUIDELINES | EXAMPLES | MAPPINGS

GUIDELINES FOR USE

<physicalDescription> is a container element that contains all subelements relating to physical description information of the resource. Data is input only within each subelement.

It is usually not necessary to include a full <physicalDescription> for every version of a resource known to exist; choose carefully which versions and elements are important. The examples given in these guidelines represent a sample of the types of data which may be important to expose.

Repeating this element is not recommended.

Specific DLF/Aquifer Guidelines

The DLF/Aquifer Implementation Guidelines for Shareable MODS Records require the use of one <physicalDescription> element, one <digitalOrigin>subelement, and at least one <internetMediaType> subelement.

Encode information in <physicalDescription> relevant to any version of a resource that is considered useful in an aggregated environment.

See the <physicalDescription> entry in the DLF/Aquifer Summary of MODS Requirements and Recommendations Table for further information on requirements of this element, its attributes, and subelements.

Aggregator information: Information in <internetMediaType>, and possibly <form> may be used by aggregators to limit searches to particular types of resources or to offer browsing. Other information in <physicalDescription> would generally be used in the record display.

Physical description is not explicitly covered in the DLF/NSDL Best Practices for Shareable Metadata External Link. However, portions of the "Types of Resources" and "Describing Versions and Reproductions" sections may be applicable.

Element Description

Attributes

altRepGroup; lang; xml:lang; script; transliteration; unit; displayLabel

See the Attributes used throughout the schema for descriptions of each.

Subelements

The following subelements are described below:

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Subelement: <form>

Definition A designation of a particular physical presentation of a resource, including the physical form or medium of material for a resource.
Attributes type; authority; authorityURI; valueURI; lang; xml:lang; script; transliteration
Subelements None

Guidelines for Use

Record the form of the digitized and analog original resources if such information will be useful. The <form> element should be used to characterize the resource itself rather than the content of the resource, which would be <genre>.

Either a controlled list of values or free text may be used.

Specific DLF/Aquifer Guidelines

The use of the type attribute is not recommended with <form> by the DLF/Aquifer Implementation Guidelines for Shareable MODS Records due to the lack of controlled values, making it of limited usefulness for aggregators.

Element Description

Attributes

type

Definition
May be used to specify whether the form concerns materials or techniques, for example:
<form type="material">oil paint</form>
<form type="technique">painting</form>
Application
There are no controlled values for the type attribute.

authority

Definition
The controlled list from which the value is taken.
Application
A list of possible authorities is available at Genre/Form Code and Term Source Codes maintained by the Library of Congress.

authorityURI

Definition
A URI uniquely identifying the vocabulary from which the controlled term has been selected, as assigned by the body responsible for the maintenance of the vocabulary.
Application
URIs identifying authorities may or may not be dereferenceable to human- or machine-readable information on the authority file, controlled vocabulary, or thesaurus.

valueURI

Definition
A URI uniquely identifying the term or controlled value from a vocabulary, as assigned by the body responsible for the maintenance of the vocabulary.
Application
URIs identifying terms may or may not be dereferenceable to human- or machine-readable records for the term.

lang; xml:lang; script; transliteration

See the Attributes used throughout the schema for descriptions of each.

Subelements

There are no subelements for <form>.

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Subelement: <reformattingQuality>

Definition Indicates an overall assessment of the physical quality of an electronic resource in relation to its intended use.
Attributes None
Subelements None

Guidelines for Use

If the resource serves more than one purpose, the element may be repeated.

The following values may be used:

  • access – The electronic resource is intended to support current electronic access to the original item (i.e., reference use), but is not sufficient to serve as a preservation copy.
  • preservation – The electronic resource was created via reformatting to help preserve the original item. The capture and storage techniques ensure high-quality, long-term protection.
  • replacement – The electronic resource is of high enough quality to serve as a replacement if the original is lost, damaged, or destroyed.

Specific DLF/Aquifer Guidelines

The DLF/Aquifer Implementation Guidelines for Shareable MODS Records state the use of this subelement is optional. The values available in MODS for this subelement reflect information useful in local environments, but not for the purposes of metadata aggregation. Aggregators are unlikely to benefit from the inclusion of this subelement in shared metadata records.

Element Description

Attributes

There are no attributes for <reformattingQuality>.

Subelements

There are no subelements for <reformattingQuality>

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Subelement: <internetMediaType>

Definition An identification of the electronic format type, or the data representation of the resource.
Attributes lang; xml:lang; script; transliteration
Subelements None

Guidelines for Use

<internetMediaType> specifies the electronic format type, such as text/html, ASCII, Postscript file, executable application, or JPEG image. The <internetMediaType> value is generally taken from a controlled list, especially from the Internet Media types (MIME types).

If a digital resource comprises multiple file types (for example, a diary that has been imaged and a text transcription made available), use a separate <internetMediaType> subelement for each.

The element may also include local x-types.

Specific DLF/Aquifer Guidelines

Since it is expected that records shared for the Aquifer initiative describe resources existing in digital versions, at least one <internetMediaType> is required by the DLF/Aquifer Implementation Guidelines for Shareable MODS Records.

Element Description

Attributes

lang; xml:lang; script; transliteration

See the Attributes used throughout the schema for descriptions of each.

Subelements

There are no subelements for <internetMediaType>.

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Subelement: <extent>

Definition A statement of the number and specific material of the units of the resource that express physical extent.
Attributes supplied; unit; lang; xml:lang; script; transliteration
Subelements None

Guidelines for Use

<extent> may be used with electronic resources, e.g. for digitized collection of slides, to show how many slides constitute the resource.

Specific DLF/Aquifer Guidelines

The DLF/Aquifer Implementation Guidelines for Shareable MODS Records strongly recommended the use of a content standard of choice if this subelement is used.

Element Description

Attributes

supplied

Definition
An indication that the extent information did not come from the resource itself.
Application
This attribute is used as supplied="yes" when the extent information has been supplied from an external source, not from the resource.

unit

Definition
Allows for more granularity within the extent element.
Application
This attribute is used to provide more granular information regarding extent by sepaprating out unit type.

lang; xml:lang; script; transliteration

See the Attributes used throughout the schema for descriptions of each.

Subelements

There are no subelements for <extent>.

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Subelement: <digitalOrigin>

Definition The method by which a resource achieved digital form.
Attributes None
Subelements None

Guidelines for Use

<digitalOrigin> may indicate the source of a digital file, which is important to its creation, use, and management.

The following values may be used:

  • born digital – A resource was created and is intended to remain in digital form.
  • reformatted digital – A resource was created by digitization of the original which was in a non-digital form (except original microforms).
  • digitized microfilm – A resource was created by digitizing a microform.
  • digitized other analog – A resource was created by digitizing an intermediate form of the original resource (but not microform) such as photocopy, transparency, slide, 2nd generation analog tapes, etc.

Specific DLF/Aquifer Guidelines

Resources incorporating pre-existing analog content with new digital content should be recorded as "born digital".

Element Description

Attributes

There are no attributes for <digitalOrigin>.

Subelements

There are no subelements for <digitalOrigin>.

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Subelement: <note>

Definition General textual information about the physical description of a resource.
Attributes type; displayLabel; lang; xml:lang; script; transliteration; typeURI
Subelements None

Guidelines for Use

Use for notes relating to the physical description of a resource that do not fit in one of the other available subelements. Documentation on material and technique used for works of art and similar materials may be recorded here.

A link may be supplied in lieu of or in addition to the <note> content.

Each note should be entered in a separate <note> subelement.

Specific DLF/Aquifer Guidelines

Use of the type attribute is not recommended due to the lack of controlled values. Use of uncontrolled values has limited usefulness for aggregators.

The displayLabel attribute may be used to indicate the preferred labeling when displayed by a metadata aggregator. However, metadata aggregators may choose to ignore this attribute.

Element Description

Attributes

type

Definition
Provides contextual information to further categorize the note information.
Application
This attribute is not controlled by a list and thus is open-ended. See MODS <note> Types for a list of physical description-related note types that have been used by MODS implementers.

typeURI

Definition
Used to indicate that a type is in the form of a URI.
Application
URIs identifying authorities may or may not be dereferenceable to human- or machine-readable information on the authority file, controlled vocabulary, or thesaurus.

ID; lang; xml:lang; script; transliteration; typeURI; displayLabel

See the Attributes used throughout the schema for descriptions of each.

Subelements

There are no subelements for <note>.

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EXAMPLES

<physicalDescription>
<note type="organization">Fixed-length, nonhierarchical; Month by carrier code and flight number</note>
</physicalDescription>
<physicalDescription>
<extent>7" x 9"</extent>
<note displayLabel="Location within resource">Between entry for April 7 and April 19, 1843</note>
</physicalDescription>
<physicalDescription>
<form authority="marcform">print</form>
<extent>ill., music ; 26 cm</extent>
<reformattingQuality>replacement</reformattingQuality>
</physicalDescription>
<physicalDescription>
<extent>1 sound disc (56 min.) : digital ; 3/4 in.</extent>
</physicalDescription>
<physicalDescription>
<extent unit=”pages”>12</extent>
</physicalDescription>

For a digitized photograph:

<physicalDescription>
<form authority="smd">photoprint</form>
<form authority="marcform">electronic</form>
<reformattingQuality>access</reformattingQuality>
<internetMediaType>image/jpeg</internetMediaType>
<extent>1 photograph</extent>
<digitalOrigin>reformatted digital</digitalOrigin>
</physicalDescription>

For a diary that has been imaged and for which a text transcription has been made:

<physicalDescription>
<form authority="marcform">electronic</form>
<form authority="marcform">print</form>
<internetMediaType>image/jpeg</internetMediaType>
<internetMediaType>text/xml</internetMediaType>
<extent>177 p.</extent>
<digitalOrigin>reformatted digital</digitalOrigin>
</physicalDescription>

For a learning web site:

<physicalDescription>
<form authority="marcform">electronic</form>
<internetMediaType>image/jpeg</internetMediaType>
<internetMediaType>text/html</internetMediaType>
<extent>5 digital files</extent>
<digitalOrigin>born digital</digitalOrigin>
</physicalDescription>

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MAPPINGS

MARC Mapping (Bibliographic)

<physicalDescription><form authority="marcform"> = MARC 21 fields 008/23 (BK, MU, CR, MX) and 008/29 (MP, VM)

<physicalDescription><form authority="marccategory"> = MARC 21 fields 007/00 values "a" through "v"

<physicalDescription><reformattingQuality> ≈ MARC 21 field 007/13 (ER)

<physicalDescription><internetMediaType> ≈ MARC 21 field 856 subfield q (Subfield q may also contain other designations of electronic format.)

<physicalDescription><extent> ≈ MARC 21 fields 300 subfields a, b, c, and e and 306 subfield a

<physicalDescription><digitalOrigin> ≈ MARC 21 field 007/11 (Antecedent/source) for electronic resources

<physicalDescription><digitalOrigin="born digital"> has no MARC equivalent, but includes 007/11 value "c"

<physicalDescription><digitalOrigin="reformatted digital"> = MARC 21 field 007/11 value "a"

<physicalDescription><digitalOrigin="digitized microfilm"> = MARC 21 field 007/11 value "b"

<physicalDescription><digitalOrigin="digitized other analog"> = MARC 21 field 007/11 value "d"

<physicalDescription><note> ≈ to the types of notes in MARC fields 340, 351, or general 500 notes concerning physical condition, characteristics, etc.

See also MARC Mapping to MODS for the <physicalDescription> element.

Dublin Core Mapping

The MODS to Dublin Core Metadata Element Set Mapping recommend mapping <physicalDescription>, <form>, <extent>, and <internetMediaType> to <dc:format>. These guidelines also recommend mapping <digitalOrigin> to <dc:format>. Each value should be mapped to a separate instance of the <dc:format> element.

MODS example expressed in Dublin Core:

<dc:format>electronic</dc:format>
<dc:format>print</dc:format>
<dc:format>image/jpeg</dc:format>
<dc:format>text/xml</dc:format>
<dc:format>177 p.</dc:format>
<dc:format>reformatted digital</dc:format>

<dc:format>electronic</dc:format>
<dc:format>image/jpeg</dc:format>
<dc:format>text/html</dc:format>
<dc:format>5 digital files</dc:format>
<dc:format>born digital</dc:format>

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Disclaimer

Last Updated: February 4, 2015