##### 3.1.6.9 unknown

The <unknown> element is an open extension that allows information architects to incorporate xml fragments that do not necessarily fit into an existing DITA use case. Processors should ignore this element unless otherwise instructed.

###### Contains

Doctype | Content model
topic, map, concept, ditabase, glossary, glossentry, glossgroup, reference, task, bookmap, classifyMap, subjectScheme, machineryTask, learningAssessment, learningBookmap, learningContent, learningMap, learningOverview, learningPlan, learningSummary | ANY

###### Contained by

Doctype | Content model
topic (base) | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence
map (base), classifyMap, learningMap | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, topicmeta, linktext, searchtitle, index-see, index-see-also, index-sort-as, b, u, i, tt, sup, sub, coords, typeofhazard, consequence
topic (technical content) | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
map (technical content) | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, topicmeta, linktext, searchtitle, index-see, index-see-also, index-sort-as, b, u, i, tt, sup, sub, coords, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
concept | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, conbody, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
ditabase | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, conbody, prereq, context, steps-informal, stepsection, cmd, info, tutorialinfo, stepxmp, choice, choptionhd, chdeschd, choption, chdesc, stepresult, result, postreq, refbody, refbodydiv, refsyn, proptypehd, propvaluehd, propdeschd, proptype, propvalue, propdesc, glossterm, glossdef, glossProperty, glossUsage, glossScopeNote, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
glossary, glossentry, glossgroup | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, conbody, glossterm, glossdef, glossProperty, glossUsage, glossScopeNote, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
reference | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, refbody, refbodydiv, refsyn, proptypehd, propvaluehd, propdeschd, proptype, propvalue, propdesc, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
task (strict), task (general) | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, prereq, context, steps-informal, stepsection, cmd, info, tutorialinfo, stepxmp, choice, choptionhd, chdeschd, choption, chdesc, stepresult, result, postreq, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
bookmap | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, topicmeta, linktext, searchtitle, person, organization, summary, printlocation, bookpartno, booknumber, index-see, index-see-also, index-sort-as, organizationname, otherinfo, addressdetails, locality, localityname, administrativearea, thoroughfare, emailaddress, url, b, u, i, tt, sup, sub, coords, typeofhazard, consequence, uicontrol, screen, codeph, codeblock, var, oper, delim, sep, pt, pd, fragref, repsep, msgph, msgblock, filepath, userinput, systemoutput
subjectScheme | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, topicmeta, linktext, searchtitle, b, u, i, tt, sup, sub, coords, typeofhazard, consequence
machineryTask | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, prereq, context, steps-informal, stepsection, cmd, info, tutorialinfo, stepxmp, choice, choptionhd, chdeschd, choption, chdesc, stepresult, result, postreq, reqcond, reqcontp, personnel, perscat, perskill, esttime, supequi, supply, spare, safecond, typeofhazard, consequence, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, uicontrol, screen
learningAssessment, learningOverview, learningSummary | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, lcIntro, lcObjectivesStem, lcObjective, lcAudience, lcTime, lcPrereqs, lcSummary, lcNextSteps, lcReview, lcResources, lcChallenge, lcInstruction, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, lcInteractionBase, lcQuestionBase, lcInstructornote, lcQuestion, lcOpenAnswer, lcFeedback, lcFeedbackCorrect, lcFeedbackIncorrect, lcAnswerContent, lcItem, lcMatchingItem, lcAreaCoords
learningBookmap | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, topicmeta, linktext, searchtitle, person, organization, summary, printlocation, bookpartno, booknumber, index-see, index-see-also, index-sort-as, organizationname, otherinfo, addressdetails, locality, localityname, administrativearea, thoroughfare, emailaddress, url, b, u, i, tt, sup, sub, coords, typeofhazard, consequence
learningContent | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, lcIntro, lcObjectivesStem, lcObjective, lcAudience, lcTime, lcPrereqs, lcSummary, lcNextSteps, lcReview, lcResources, lcChallenge, lcInstruction, prereq, context, steps-informal, stepsection, cmd, info, tutorialinfo, stepxmp, choice, choptionhd, chdeschd, choption, chdesc, stepresult, result, postreq, conbody, refbody, refbodydiv, refsyn, proptypehd, propvaluehd, propdeschd, proptype, propvalue, propdesc, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, lcInteractionBase, lcQuestionBase, lcInstructornote, lcQuestion, lcOpenAnswer, lcFeedback, lcFeedbackCorrect, lcFeedbackIncorrect, lcAnswerContent, lcItem, lcMatchingItem, lcAreaCoords
learningPlan | data, title, navtitle, shortdesc, desc, p, note, lq, q, sli, li, itemgroup, dthd, ddhd, dt, dd, fig, figgroup, pre, lines, ph, alt, object, stentry, draft-comment, fn, indexterm, index-base, cite, xref, entry, author, source, publisher, copyrholder, category, metadata, prodname, brand, series, platform, prognum, featnum, component, searchtitle, abstract, body, bodydiv, section, sectiondiv, example, prolog, linktext, linkinfo, lcIntro, lcObjectivesStem, lcObjective, lcAudience, lcTime, lcPrereqs, lcSummary, lcNextSteps, lcReview, lcResources, lcChallenge, lcInstruction, lcClient, lcPlanTitle, lcCIN, lcModDate, lcDelivDate, lcPlanSubject, lcPlanDescrip, lcPlanPrereqs, lcGeneralDescription, lcGoals, lcNeeds, lcValues, lcOrgConstraints, lcEdLevel, lcAge, lcBackground, lcSkills, lcKnowledge, lcMotivation, lcSpecChars, lcWorkEnvDescription, lcPlanResources, lcProcesses, lcTaskItem, lcAttitude, lcPlanObjective, lcJtaItem, lcGapItemDelta, lcLearnStrat, lcAssessment, lcDelivery, lcLMS, lcNoLMS, lcHandouts, lcClassroom, lcOJT, lcConstraints, lcW3C, lcPlayers, lcGraphics, lcViewers, lcResolution, lcFileSizeLimitations, lcDownloadTime, lcSecurity, b, u, i, tt, sup, sub, coords, index-see, index-see-also, index-sort-as, lcInteractionBase, lcQuestionBase, lcInstructornote, lcQuestion, lcOpenAnswer, lcFeedback, lcFeedbackCorrect, lcFeedbackIncorrect, lcAnswerContent, lcItem, lcMatchingItem, lcAreaCoords

###### Inheritance

- topic/unknown

###### Example

This example features a specialized <unknown> element that includes other non-DITA content. If this specialization is imported to a DTD or schema, the DTD or schema will need to handle declaring the new elements or any namespaces.

    <body>
      <my-unknown class="+ topic/unknown mything/my-unknown ">
        <thing value="4"/>
        <otherthing value="16"/>
      </my-unknown>
    </body>

###### Attributes

Name | Description | Data Type | Default Value | Required?
univ-atts attribute group (includes select-atts, id-atts, and localization-atts groups) | A set of related attributes, described in 3.4.1.3 univ-atts attribute group |  |  |
global-atts attribute group (xtrf, xtrc) | A set of related attributes, described in 3.4.1.2 global-atts attribute group |  |  |
class, outputclass | Common attributes described in 3.4.1.9 Other common DITA attributes |  |  |

Previous Topic: 3.1.6.8 state

Next Topic: 3.1.7 Legacy conversion elements

Parent Topic: 3.1.6 Specialization elements

Sibling Topics:

3.1.6.1 boolean

3.1.6.2 data

3.1.6.3 data-about

3.1.6.4 foreign

3.1.6.5 index-base

3.1.6.6 itemgroup

3.1.6.7 no-topic-nesting

3.1.6.8 state