MODS Element	Attributes	Subelements
<mods:physicalDescription>	@type -- <mods:form>, <mods:note> @authority -- <mods:form> @unit -- <mods:extent>	<mods:form> <mods:reformattingQuality> <mods:internetMediaType> <mods:extent> <mods:digitalOrigin> <mods:note>

Usage Guidelines

1. At least one <physicalDescription> element, with one <digitalOrigin> and one <internetMediaType> are always required.        
2. It is not necessary to include a full physical description of every version of a resource known to exist. Usually, it is sufficient to include one description of the digital form and one description of the analog form, if it varies significantly from the digital form.
3. <reformattingQuality> takes only: access, preservation, and replacement.
4. <internetMediaType> must take values from the MIME Media Types list, expressed in the format type/subtype format. Use multiple iterations of <internetMediaType> for resources that comprise multiple file types.
5. Use RDA when determining the extent of a resource.
6. Include RDA media, content, and carrier types in a series of <form> elements.
7. <digitalOrigin> takes the following values:

born digital

reformatted digital

digitized microfilm

digitized other analog

8. If a resource incorporates pre-existing analog content with new digital content, the <digitalOrigin> should be “born digital.”

Elements

<physicalDescription>

Required: Y

Repeatable: N

Definition: Describes the physical attributes of the information resource. <physicalDescription> is a wrapper element that contains all subelements relating to the physical description of the resource being described.

<form>

Required: R

Repeatable: N

Definition: A designation of a particular physical presentation of a resource, including the physical form or medium of material for a resource.

Attributes:

type: this attribute takes the following values:

content

media

carrier

authority (required if applicable): takes values from Genre/Form and Term Source Codes.

<reformattingQuality>

Required: N

Repeatable: N

MARC: 007/13

Definition: Indicates an overall assessment of the physical quality of an electronic resource in relation to its intended use.

<internetMediaType>

Required: Y

Repeatable: Y

MARC: 856 $q

Definition: An identification of the electronic format type, or the data representation of the resource.

<extent>

Required: R

Repeatable: Y

MARC: 300 $a, $b, $c, $e, 306 $a

Definition: A statement of the number and specific material of the units of the resource that express physical extent.

<digitalOrigin>

Required: Y

Repeatable: N

MARC: 007/11

Definition: The method by which a resource achieved digital form.

<note>

Required: R

Repeatable: Y

MARC: 340, 351, 500

Definition: General textual information about the physical description of a resource.

Examples

<!-- For a digitized photograph -->

<mods:physicalDescription>
  <mods:form authority="smd">photoprint</mods:form>
  <mods:form authority="marcform">electronic</mods:form>
  <mods:form authority="rdacontent" type="content">still image</mods:form>
  <mods:form authority="rdamedia" type="media">computer</mods:form>
  <mods:form authority="rdacarrier" type="carrier">online resource</mods:form>
  <mods:internetMediaType>image/jpeg</mods:internetMediaType>
  <mods:extent>1 photograph</mods:extent>
  <mods:digitalOrigin>reformatted digital</mods:digitalOrigin>
</mods:physicalDescription>

<!-- For a diary that has been imaged and for which a text transcription has been made-->

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

<!-- For a learning web site -->

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