Host Content Language (HCL) is a language to structure and describe generic content for human consumption sent over HTTP or a similar other method of transfer. The objective is to provide a vocabulary and structure that is semantic first and accessible second. The language allows for the integration of any other XML vocabulary as a namespace plugin. Visual Color Key (for visual users) element child element element group child group attribute attribute group reusable complex type element name element group name attribute name attribute group name element example element's parent hcl Element hcl is the root element of a HCL document. < hcl version="1.0" document-type="application/hcl+xml">↔< /hcl> about (required) content (required) version (required) document-type (required) version Attribute version is required with a fixed value of "1.0". version="1.0" document-type Attribute document-type is required with a fixed value of "application/hcl+xml". document-type="application/hcl+xml" about Element about is a child of root element < hcl>. This element represents a container of meta-data that either contains additional processing instructions for the user-agent software or describes the whole document. < about>< page-title/>< character/>< language/>< /about> no attributes page-title (required) character (required) language (required) user-agent (optional) presentation (optional) custom namespace prefixed elements (optional) page-title Element page-title is a child of element < about>. This element represents a title of the entire document for external use by the user-agent software and web crawling software. This elements stores a normalized string value. < page-title>External title representing the entire document.< /page-title> no attributes no child elements character Element character is a child of element < about>. This element contains the value of the character encoding reference the author intended the document to be processed in accordance with by the user-agent software. This value of this element should match the character encoding actually used by the author to write the document. < character>utf-8< /character> This element may except the following values: iso-8859-1 iso-8859-2 iso-8859-3 iso-8859-4 iso-8859-5 iso-8859-6 iso-8859-7 iso-8859-8 iso-8859-9 iso-8859-10 iso-8859-15 iso-8859-16 iso-8859-jp iso-8859-jp-2 iso-8859-kr utf-8 utf-16 utf-16be utf-16le utf-32 utf-32be utf-32le usc-2 usc-2be usc-2le usc-4 usc-4be usc-4le iso-10646-ucs-2 iso-10646-ucs-4 shift-jis euc-jp no attributes no child elements language Element language, a child of < about> accepts values conforming to XML Schema language simple data type, which is further expanded in RFC 3066. This element serves to identify the default natural, or human written, language of the entire document. < language>en-US< /language> no attributes no child elements user-agent Element user-agent is a child of element < about>. This element represents a title of the entire document for external use by the user-agent software and web crawling software. This elements stores a normalized string value. < user-agent process="thing to process" function="how to process that thing"/> no child elements function (required) process (required) function Attribute function is a required attribute of element user-agent containing a unique name value. function="distribution" process Attribute process is a required attribute of element < user-agent> containing a normalized string. process="British Virgin Islands" presentation Element presentation is a child of element < about>. This element is a container of stylesheet elements. < presentation>< stylesheet/>< /presentation> no attributes stylesheet (1 or more required) stylesheet Element stylesheet is a child of element < presentation>. This element serves to specify a stylesheet. It excepts only a URI as content. If the content results in text that is not a URI or is a URI that cannot be resolved the failing < stylesheet> must be ignored. < stylesheet namespace="car" style-type="text/css">http://travelocity.com/assets/css/car.css< /stylesheet> no child elements style-type (required) style-namespace (required) media (optional) style-type Attribute style-type is a required attribute of style-type defines how the requested stylesheet must be processed. The appropriate values are: style-type="text/css" text/css application/xslt+xml style-namespace Attribute style-namespace is a required attribute of stylesheet that defines a namespace prefix to designate which style reference is associated with which stylesheet. style-namespace="hotels" media Attribute media is an optional attribute of stylesheet that defines the intended output media the stylesheet is intended to provide presentation for. If this attribute is not specified a value of "screen" must be assumed. Acceptable values are: media="braille" List defined by W3C: http://www.w3.org/TR/CSS2/media.html all aural braille embossed handheld print projection screen tty tv content Element content is a child of root element < hcl>. This element serves as a container for all human consumable content. < content>↔< /content> complex-blocks simple-blocks custom namespace prefixed elements (optional) script (optional and may occur more than once, but must be the last child element of parent < content>) core-attrs inter-attrs core-attrs A group of universally allowed attributes. id (optional) style (optional) title (optional) role (optional) core-attrs-uri A group of universally allowed attributes plue attribute "uri". id (optional) style (optional) title (optional) role (optional) uri (optional) inter-attrs A group of internationalization attributes. direction (optional) orientation (optional) wrap (optional) section-language (optional) cell-attrs A group of attributes for < table-cell> and < head-cell< elements. span-column (optional) span-row (optional) id Attribute id is a member of core-attrs attribute group and core-attrs-uri attribute group. It allows a unique name value. If the value supplied is either not unique or a non-colonized name an error will be reported. id="uniqueToken" style Attribute style is a member of core-attrs attribute group and core-attrs-uri attribute group that stores a name value to reference a presentation property from a stylesheet. The supplied value does not have to be unique. It does, however, have to be prefixed with the appropriate namespace prefix as specified in the < style-namespace> element of the stylesheet it is referencing. style="cars:subtitle" title Attribute title is a member of core-attrs attribute group and core-attrs-uri attribute group that stores a string value to represent any additional data an author may wish to supply to the markup without that content being explicitly processed as content output. The value supplied in this attribute will be available for data processing at the user-agent for the user's benefit, such as a tool tip, even if it is not explicitly parsed into the content. title="The content of this element updated 31 October 2009 by employee #289532." role Attribute role is a member of core-attrs attribute group and core-attrs-uri attribute group that stores a name value, which may or may not be a namespace prefixed name and is not required to be unique. The value of this attribute can be used to include functional values from other namespaces, such as ARIA or RDF. If no namespace prefix is supplied for the given value then a semantic quality must be presumed, where the intent of value is to more specificly define the element opposed to the generic element name. A value should not be applied that contradicts or challenges the definition of the element name. role="catalogue:undergraduate" uri Attribute uri is a member of core-attrs-uri attribute group and is a required attribute for several elements. This attribute supplies a URI value for hyperlinking. If this attribute is present a hyperlink must exist. If this attribute is not present a hyperlink must not exist. This value of this attribute should be a well formed URI according to RFC 3986 or RFC 2368 for email addresses. The value of this attribute does not have to resolve to a resource. uri="http://www.travelocity.com/" direction Attribute direction, a member of inter-attrs attribute group, defines the direction of text within a given container. direction="br" There are two possible values: tl br Value "tl" means that text starts from either the left or top depending upon the vertical or horizontal orientation of text in the given block. Value "br" indicates starts from the right or bottom of the containing block. orientation Attribute orientation, a member of inter-attrs attribute group, defines the directional flow of text, horizontally or vertically, within the given block. orientation="vertical" There are two possible values: horizontal vertical wrap Attribute wrap, a member of inter-attrs attribute group, defines the direction in which text wraps onto a new line. wrap="reverse" The appropriate values are: standard reverse none A value of standard will cause text to wrap down if it is horizontally oriented or to the left if it is vertically oriented. The value "reverse" forces text to wrap in the direction opposite of the "standard" value. The value "none" prevents text from wrapping. If the value "none" is applied and the text line exceeds the width of the parent container, or height for vertically oriented text, then the containing block must stretch to accomodate the contained text. section-language The attribute section-language, a member of inter-attrs attribute group, defines a change of natural human language from the default natural human language specified in the < languge> element. section-language="en-US" refer Attribute refer must have a value match the id attribute value of another element. If the supplied value for the refer attribute does not match the value of an id attribute on another element an error will be produced. refer="vacationID-3456" span-column Attribute span-column, a member of cell-attrs attribute group, allows a < table-cell> or < head-cell> element to span multiple columns. The value for this attribute must be a positive integer. span-column="3" span-row Attribute span-row, a member of cell-attrs attribute group, allows a < table-cell> or < head-cell> element to span multiple rows. The value for this attribute must be a positive integer. span-row="2" scope Attribute scope is used in table < head-cell> elements to determine which < table-cell> elements the < head-cell> is providing a heading for. scope="group-column" The acceptable values are: column row group-column group-row The value "column" indicates the < head-cell> is providing meta-data for cells in the first single column occupied by that < head-cell> element. The value "row" indicates the < head-cell> is providing meta-data for the cells in the first single row occupied by that < head-cell> element. The value "group-column" indicates the < head-cell> is providing meta-data to all columns occupied by a < head-cell> element. The value "group-row" indicates the < head-cell> provides meta-data for all rows occupied by that < head-cell> element. long-form Attribute long-form, used with element < short>, defines the designated expanded representation of condensed text, such as an abbrievation or an acronymn. long-form="representational state transfer" complex-blocks - (choice of the following) A group of block elements capable of containing other block elements, but not text. list-group table section form simple-blocks - (choice of the following) A group of block elements capable of containing text, but not other block elements. block-code block-quote citation heading object paragraph separator simple-blocks-type inline (optional, but may occur more than once) core-attrs inter-attrs inline - (choice of the following) A group of elements capable of containing text only, except for element < format>. xfm:Form.Controls short button cite emphasis identifier quote format strong title object-group A group of elements for the < object> element and < nav-object> element. object-text (required) object-uri (required) object-type (required) inline (optional, but may occur more than once) inline-base core-attrs-uri inline-type format-type format (optional, but may occur more than once) core-attrs-uri list-group - (choice of the following) A group of elements that are containing blocks for various forms of lists. define-list navigation-list order-list unorder-list nesting-block (unlimited choice of the following) complex-blocks simple-blocks custom namespace prefixed elements (optional) define-list Element define-list is a member of list-group element group. This element is a list of definition items. < define-list>< define-item/>< /define-list> define-item (required and may occur more than once) core-attrs define-item Element define-item, a child of < define-item>, is a single definition item in a definition list. This child elements are both allowed more than once because the relationship between a term and potential definitions may be one to one or one to many. A single definition may also represent multiple separate terms and as a result the relationship between a definition and its terms may be one to one or one to many. < define-item>< define-term>a term to define< /define-term>< definition>The term's definition< /definition>< /define-item> define-term (required and may occur more than once) definition (required and may occur more than once) core-attrs define-term Element define-term, a child of < define-item>, stores a defining term in the definition item. The value for this element must be a normalized string, which allows a term of more than one word to be represented. < define-term>cognitive conservatism< /define-term> core-attrs-uri inter-attrs definition Element definition, a child of < define-item>, stores a definition in the definition item. < documentation>A behaviorial state where a subject demonstrates an < emphasis>inability< /emphasis> to alter prior formed conclusions dispite rational evidence challenging such conclusions.< /definition> inline core-attrs inter-attrs navigation-list Element navigation-list, a member of list-group element group, allows for the creation of a list of child elements whose purpose is to provide a system of navigation, such as a menu or site map. < navigation-list>< navigation-item/>< navigation-list> heading (optional, but is a choice between a < heading> element and a < identifier> element) identifier (optional, but is a choice between a < heading> element and a < identifier> element) navigation-item (required and may occur more than once) core-attrs navigation-item Element navigation-item, a child of < navigation-list>, is a single navigation item in a navigation list. < navigation-item>< navigation-object>< /navigation-item> navigation-object (required, but is a choice between a < navigation-object> element and a < navigation-text> element) navigation-text (required, but is a choice between a < navigation-object> element and a < navigation-text> element) core-attrs uri (required) navigation-object Element navigation-object, a child of < navigation-item>, stores elements necessary to process a media object specifically used in a navigation list. < navigation-object>< object-text>some text< object-text>< object-uri>http://www.travelocity.com/image.jpg< object-uri>< object-type>< image>jpeg< image>< /object-type>< /navigation-object> object-text (required) object-uri (required) object-type (required) inter-attrs core-attrs object-text Element object-text stores a text representation of the media object requested by peer elements. The default presentation of this element is a decision left to the user-agent software, which means the text may appear by default as in a caption or may be hidden from visible view by default. If this element is not visible by default it should become visible if the requested media cannot be resolved or cannot be processed according to its defined mime-type. < object-text>This is text that assists accessibility for persons unable to process the intended media and acts as alternate content.< /object-text> no child elements no attributes object-uri Element object-uri stores the URI location of a media object. It is not required that the provided URI be resolvable, but the URI must be well formed in accordance with RFC 3986. If the URI cannot be resolved then the text stored in the adjacent < object-text> element must be rendered as content. < object-uri>http://www.travelocity.com/assets/images/car0567392.swf< /object-uri> no child elements no attributes object-type Element object-type contains the mime type definition of the intended media. The media must be executed only according this specified type. If the media cannot be specified according to this media type then it must not be processed and the text stored in the adjacent < object-text> should be parsed as content instead. This element is of custom type "mime-type" as defined in the included mime.xsd schema. < object-type>< video>H264< /video>< /object-type> no attributes navigation-text Element navigation-text, a child of navigation-item, stores text that is to represent a text hyperlink in a navigation list. < navigation-text>Menu Link Text< /navigation-text> no child elements inter-attrs core-attrs order-list Element order-list, a member of list-group element group, is an ordered list where each list item is enumerated in the meta-data so that the relative placement of a particular list item relevant to a different list item of the same list is data valid to the description of the list items. < order-list>< list-item/>< /order-list> heading (optional, but is a choice between a < heading> element and a < identifier> element) identifier (optional, but is a choice between a < heading> element and a < identifier> element) list-item (required and may occur more than once) core-attrs unorder-list Element unorder-list, a member of list-group element group, is an unorderd list where each list item is not enumerated in the list. This allows all list items to be of equal prominance and standing with regard to each of their relative positions in the list's order of items. < unorder-list>< list-item/>< /unorder-list> heading (optional, but is a choice between a < heading> element and a < identifier> element) identifier (optional, but is a choice between a < heading> element and a < identifier> element) list-item (required and may occur more than once) core-attrs list-item Element list-item, a child of < order-list> and < unorder-list>, is a single listed item of either an ordered list or an unorderd list. This element may contain simple block elements or may contain text and inline elements. < list-item>An < strong>item< /strong> in a list.< /list-item> simple-blocks (choice between simple-blocks group and inline group) inline (choice between simple-blocks group and inline group, inline group elements may occur more than once) core-attrs inter-attrs form Element form, a member of complex-blocks element group, serves as a complex block container for XForms 1.1 model definitions and a complex block container for form elements and simple blocks. < form>< xfm:model/>< form-body/>< /form> no attributes xfm:model (required) form-body (required) form-body Element form-body, a child of < form>, represents the content body of the form available for consumption and interaction from participants of the user-agent software. < form-body>↔< /form-body> list-group (optional) simple-blocks (optional) xfm:UI.Common (optional) table (optional) core-attrs table Element table, a member of complex-blocks element group, is a grid organized collection of data where units of that grid are referred to as cells. < table>< head-row/>< table-row/>< table-row/>< /table> head-row (optional, but must occur first) table-row (required and may occur more than once) core-attrs head-row Element head-row, a child of < table>, is an optional structural component of a table where the contained child elements represent specific meta-data to the table and not raw data. < head-row>< head-cell/>< head-row> head-cell (required and may occur more than once) core-attrs head-cell Element head-cell, a child of < head-row> or < table-row>, contains meta-data that describes other cells in the table. < head-cell>cell heading< /head-cell> simple blocks (choice between simple-blocks group and inline group) inline (choice between simple-blocks group and inline group, inline group elements may occur more than once) scope (optional) cell-attrs core-attrs inter-attrs table-row Element table-row, a child of < table> is a row in a table that is intended to contain data cells. Cells for meta-data, < head-cell>, are allowed to provide more granular description of data. < table-row>< head-cell/>< table-cell/>< table-cell/>< /table-row> head-cell (choice of < head-cell> or < table-cell>) table-cell (choice of < head-cell> or < table-cell>) core-attrs table-cell Element table-cell, a child of element < table-row>, is a single data unit container for a formal table. < table-cell>< block-quote>some text< /block-code>< /table-cell> simple-blocks (choice between simple-blocks group and inline group) inline (choice between simple-blocks group and inline group, inline group elements may occur more than once) cell-attrs core-attrs inter-attrs section Element section, a member of complex-blocks element group, is a section or division of content where that content represents a contextual difference from other content in the document. Section is of custom type, nesting-block. < section>< heading/>< paragraph/>< paragraph/>< section/>< /section> core-attrs block-code Element block-code, a member of simple-blocks element group and of custom type simple-blocks-type, is a container for storing sample code as content published to the user. < block-code>Sample < emphasis>code< /emphasis> would go here.< /block-code> block-quote Element block-code, a member of simple-blocks element group and of custom type simple-blocks-type, is a container for storing content that represents a large continuous quote or paraphase of content. < block-quote>A long quote would go here.< /block-quote> citation Element citation, a member of simple-blocks element group, is a container for storing a citation to an external source. The "id" attribute is required on this element so that it can be conviently referrenced in the content through use of inline element < cite>. < citation id="MMLSpecification">Cheney, Austin. "Mail Markup Language", Travelocity LLC, April 2009. < strong uri="http://mailmarkup.org/mml.txt">http://mailmarkup.org/mml.txt< /strong>< /citation> inline (optional, but may occur more than once) id (required) style (optional) title (optional) role (optional) inter-attrs heading Element heading, a member of simple-blocks element group and of custom type simple-blocks-type, is a container for storing content that represents a formal heading or section title. It is strongly recommended that a heading be included directly after the opening tag of any complex block. < heading>A heading would go here.< /heading> object Element object, a member of simple-blocks element group, allows for the processing of a media object directly into the content of the page. A media object may be text, audio, video, or any other form of non-textual communication interface or binary large object (BLOB). < object>< object-text>text< /object-text>< object-uri>http://wwwl.travelocity.com/hotels.jpg< /object-uri>< object-type>< image>jpeg< /image>< /object-type>< /object> object-group inter-attrs core-attrs paragraph Element paragraph, a member of simple-blocks element group and of custom type simple-blocks-type, is a container for storing content that represents a series of statements that together make up a single coherent thought. < paragraph>This is a content statement.< /paragraph> separator Element separator, a member of simple-blocks element group and of custom type simple-blocks-type, exists to provide a break point between peer blocks of content where that separation might not be otherwise clear. This element may contain text to provide instructions that further expand upon the element's objective of block separation. < separator>End of article, please return to the main menu.< /separator> short-type long-form (required) core-attrs-uri short Element short, a member of inline element group and of custom complex type short-type, is an inline element for defining condensed text, such as an acronymn or abbreviation. < short long-form="ain't ready to be a marine yet">army< /short> button-type refer (optional) core-attrs-uri button Element button, a member of inline element group and of custom complex type button-type, allows a button to be placed into the content. The functionality of that button may address any needs of the document author, however its text label should come only from the text contained by the button element. < button>text that would appear on a button< /button> cite-type refer (required) core-attrs cite Element cite, a member of inline element group and of custom complex type cite-type, defines text as a cite linked to a citation. The refer attribute is required and must have a value that matches the id attribute value of a citation element in the current document. < cite refer="MMLSpecification">Mail Markup Language< /cite> emphasis Element emphasis, a member of inline element group and of custom complex type inline-type, describes important text or text that demands more attention than the text around it. < emphasis>This text is important.< /emphasis> identifier-type refer (required) core-attrs-uri identifier Element identifier, a member of inline element group and of custom complex type identifier-type, describes text that represents some other element such as text for a form control or text that describes a block of content without representing a more formal heading. The refer attribute is required and must refer to the id attribute value of another element. < identifier refer="sectionFooter">This text describes and references to sectionFooter.< /identifier> quote Element quote, a member of inline element group and of custom complex type inline-type, describes a quotation apart from the text content around it. < quote>This text is a quotation.< /quote> format Element format, a member of inline element group and of custom complex type format-type, provides no semantic value. This element is provided to allow functional considerations without alteration of semantic interpretation onto the content. This element is unique in that it is an line element, but it may also have another format element as a child element. < format>Allows for presentation without semantic alteration.< /format> strong Element strong, a member of inline element group and of custom complex type inline-type, describes text is that equivalent to a emotional distress, boldly spoken text, or a shout. Its text should be considered alarming and emergent compared to the text around it, but not superior. Superior text is described by the < emphasis> tag. < strong>Oh no!< /strong> title Element title, a member of inline element group and of custom complex type inline-type, describes a formal work or creative body. < title>Julius Caesar< /title> by William Shakespeare First draft completed by Austin Cheney on 27 October 2009.