1. MODS What is MODS: When is MODS use:
Stands for Metadata Object Descriptive Schema
MODS is an XML descriptive metadata standard.
Uses the XML schema language of the W3C
MODS was derived from MARC (which is another standard for representation of bibliographic information)
More specifically, MODS uses a subset of MARC data elements
When is MODS use:
MODS will be used for descriptive metadata, in other words, MODS will be help to identify resources such as a bibliographic data.
Extension schema to METS

2. MODS Schema Attributes
Language Attributes
xml:lang – is an XML standard attribute that defines the language individual elements may use
Date Attributes
encoding: refers to the values that identify the format of the dates, for instance, “w3cdtf” refers to dates that use the pattern: YYYY-MM-DD, as defined by the W3C.
Repeatable: refers to whether or not the elements can be used more than one time to describe information about a rendition.

3. MODS Top-Level Elements
Top-level elements in MODS, are element names without a hierarchy, meaning that these may or may not have sub-elements but are not sub-elements of any other element.
Sub-elements refers to elements that fall under a top-level elements
The only exception where all MODS elements are sub-elements is under <relatedItem> container, this will be explained later with an couples of examples.

4. MODS Top-Level Elements
title Info
name
typeOfResource
genre
originInfo
language
physicalDescription
abstract
tableOfContents
targetAudience
note
subject
classification
relatedItem
identifier
location
accessCondition
part
extension
recordInfo

5. MODS Required Elements
Required elements are items that are must be provided according to implementation guidelines for MODS encoding practices.
Based on this, my understanding is that these elements are essential in order to assemble the archive

6. MODS Required Elements
titleInfo
typeOfResource
originInfo
physicalDescription
location
accessCondition
recordInfo
language (required if language is primary to the resource)
subject (required if applicable)

7. MODS Required Elements Example 1
Taken from the mods.xml that Kate send to us:
titleInfo
Information such as the title of the resource.
The attribute type indicates the resource type of title. For example, “alternative” refers to a different title that further identifies the resource.
For example:
<titleInfo>
<title>To increase Federal Pell Grants for the children of fallen public safety officers, and for other purposes.</title>
</titleInfo>
<titleInfo type="alternative">
<title>Officer Daniel Faulkner Children of Fallen Heroes Scholarship Act of 2010</title>
<title>S (IS)</title>

8. MODS Required Elements Example 2
Taken from the mods.xml that Kate send to us:
originInfo
Information that pertains to the origin of the resource such as publisher, date published, how the resource was issued for instance, “monographic “means that it was released in one part or a finite number of parts.
For example:
<originInfo>
<publisher>U.S. Government Printing Office</publisher>
<dateIssued encoding="w3cdtf"> </dateIssued>
<issuance>monographic</issuance>
</originInfo>

9. MODS Required Elements Example 3
Taken from the mods.xml that Kate send to us:
physicalDescription
describes the physical attributes of the resource such as general text based information about the resource (for example “type” is an attribute that gives more detail to the general text)
describes the method use to achieve digital form of the resource (for example “born digital” indicates that this particular archive was created and must remain in digital form)
describes the number of units that make up the resource
It is not repeatable

10. MODS Required Elements Example 3 continue
For example
<physicalDescription>
<note type="source content type">deposited</note> <digitalOrigin>born digital</digitalOrigin>
<extent>7 p.</extent>
</physicalDescription>

11. MODS Required Elements Example 4
Taken from the mods.xml that Kate send to us:
location
Identifies the repository holding the resource
displayLabel is an attribute the provides information associated with the location
access is an attribute that indicates the type resource that will be accessed via the URL link, for instance, the value “raw object” means that the URL is a direct link to the resource.
For example:
<location xmlns:exslt="
<url displayLabel="HTML rendition" access="raw object">
<url displayLabel="PDF rendition" access="raw object">
<url displayLabel="XML rendition" access="raw object">
</location>

12. MODS Required Elements Example 5
Taken from the mods.xml that Kate send to us:
recordInfo
Provides information about the metadata of the original record such as who created it or modified it, date it was created (encoding – denotes the format of the date)
Provides information about the date it was last modified, contains the organization and the system control number assigned to it, shows the origin of the MODS record, and the language (can be used to represent more than one language)
It is not repeatable.

13. MODS Required Elements Example 5 continue
For example
<recordInfo>
<recordContentSource authority="marcorg">DGPO</recordContentSource>
<recordCreationDate encoding="w3cdtf"> </recordCreationDate>
<recordChangeDate encoding="w3cdtf"> </recordChangeDate
<recordIdentifier source="DGPO">BILLS-111s3880is</recordIdentifier>
<recordOrigin>machine generated</recordOrigin>
<languageOfCataloging> <languageTerm type="code" authority="iso639-2b">eng</languageTerm>
</languageOfCataloging>
</recordInfo>
type attribute “identifies what type of <languageTerm> is recorded”, for example, “the value used to express language” in a coded term is code, meaning that it uses values from a controlled list
authority attribute, refers to a value taken from a controlled list, for example “iso639-2b” refers to a bibliographic language code from ISO 639-2
In <recordContentSource>, the value “marcorg” given to authority attribute indicates that the value from of a MARC Code list. If the authority attribute is not used, the value is presumed to be textual.

14. MODS Required Elements– Without Example
accessCondition - <accessCondition>
Information pertaining to the permission of accessibility of the resource
Subject - <subject>
Information detailing the specific topic of the resource
typeOfResource - <typeOfResource>
Information describing the form of the resource content

15. MODS Recommended Elements
Recommended elements are items that the implementer may ignore as long he or she have taken into account the consequences of doing so
The recommended elements are:
genre
abstract – <abstract>
“A summary of the content of the resource”
identifier

16. MODS Recommended Elements Example 1
Taken from the mods.xml that Kate send to us:
genre
Gives more specific terms to the form of the resource content used in typeOfResource
Again, an interesting attribute of genre is “authority”, which refers to the controlled list from which the value is taken, in the case below the value “marcgt” refers to MARC (another standard for representation of bibliographic information) genre terms
For example:
<genre authority=“marcgt">government publication</genre>

17. MODS Recommended Elements Example 2
Taken from the mods.xml that Kate send to us:
identifier
refers to a unique standard number or code that identifies a resource
type is attribute of identifier refers to the identifier being used, in this case "local" refers to a locally define identifier
For example:
<identifier type="local">V0b002ee180b003e5</identifier>

18. MODS Recommended If Applicable
Recommended If Applicable refers to an item that can be applied to the resource, again the implementer may ignore as long he or she have taken into account the consequences of doing so

19. MODS Recommended IF Applicable
name
tableOfContents
targetAudience
note
relatedItem
part

20. MODS Recommended IF Applicable Example 1
Taken from the mods.xml that Kate send to us:
name
Provides information such as the name of the resource within the <namePart> tags; the type attribute indicates whether the name value is personal, corporate, conference or family
<role> defines the relationship of the name to the resource; the value “authority” refers to code of authoritative sources, in this case “marcrelator” refers to the MARC relators list
For example:
<name type="corporate">
<namePart>United States Government Printing Office</namePart>
<role>
<roleTerm authority="marcrelator" type="text">printer</roleTerm>
<roleTerm authority="marcrelator" type="code">prt</roleTerm>
</role>
<roleTerm authority="marcrelator" type="text">distributor</roleTerm>
<roleTerm authority="marcrelator" type="code">dst</roleTerm>
</name>

21. MODS Recommended IF Applicable Example 2
Earlier, I mentioned that there was an exception where all MODS elements are sub-elements of <relatedItem>
relatedItem
May be best used for complex objects that may need more detail descriptive information, for example a CD with several tracks
the type attribute describes the association between the resource in the MODS record and <relatedItem>, for example “isReferencedBy” are references or citations of the content of the resource

22. MODS Recommended IF Applicable Example 2 continue…
For example (Taken from the mods.xml that Kate send to us):
<relatedItem type="isReferencedBy" xmlns:exslt="
<identifier type="USC citation">20 U.S.C. 1070a(b)(2)</identifier>
<identifier type="USC citation">20 U.S.C. 1087mm(b)</identifier>
</relatedItem>

23. MODS Recommended IF Applicable – Without Examples
tableOfContents - <tableOfContents>
Information describing the content of the resource
targetAudience - <targetAudience>
Information describing who should read the resource
part - <part>
Information that identifies physical part of a resource.

24. MODS Optional Elements
Optional elements are items that may be used at the implementer’s discretion
<extension>
is a container used to include information that is not MODS
For example, information that is local to the creator of the data
Another example, is to extend MODS to allow another XML schema to handle information about the resource

25. MODS Optional Element Example 1
Taken from the mods.xml that Kate send to us:
<extension>
<collectionCode>BILLS</collectionCode>
<searchTitle>To increase Federal Pell…. searchTitle>
<category>Bills and Statutes</category>
<waisDatabaseName>111_cong_bills</waisDatabaseName>
<branch>legislative</branch>
<dateIngested> </dateIngested>
</extension>

26. MODS Optional Element Example 2
<classification>
a code that identifies to the subject of the resource
the authority attribute is required, because it identifies such code. For instance, “sudocs” refers to Superintendent of Documents classification system.
For example:
<classification authority="sudocs">Y 1.6:</classification>

27. mods.xml Header
xmlns:xlink – indicates that the namespace gets access to the Xlink attributes and features
xmlns – refers to a namespace, which is a unique value (Note: the xml parser does not use the namespace URI to look up information)
version – refers to the MODS version
xsi:schemaLocation – the first value refers to the namespace that will be used and the second value refers to the location of the schema that will be used, in this case it is the MODS XML schema.
ID – refers to the object identifier that will be used to refer to this xml file inside mets.xml
Example:
<mods xmlns:xlink="
xmlns:xsi="
xmlns="
version="3.3“
xsi:schemaLocation="
ID="D09002ee180b004da">

28. Additional Information On Using mods.xml
When will mods.xml be used by METS (aip.xml) ?
METS will use the mods.xml to encode descriptive metadata.
METS uses a pointer to the metadata that is located outside of the METS document. More specifically, it uses a xlink:href to indicate the location of such file.
Example:
<!-- MODS object  -->
<mets:dmdSec ID="DMD_OTHER">
<mets:mdRef ID="D09002ee180b004da" MDTYPE="MODS" MIMETYPE="text/xml" LOCTYPE="URL" xmlns:xlink=" xlink:href="file:/mods.xml" />
</mets:dmdSec>

29. References
Digital Library Federation/Acquifer Implementation Guidelines for Shareable MODS Records
MODS User Guidelines
MODS: Uses and Features
W3C Schools