This is the top node of the formatting object tree. It holds an fo:layout-master-set formatting object (which holds all masters used in the document), an optional fo:declarations, and one or more fo:page-sequence objects. Each fo:page-sequence represents a sequence of pages that result from formatting the content children of the fo:page-sequence. The fo:layout-master-set is a wrapper around all masters used in the document. This includes page-sequence-masters, page-masters, and region-masters. The fo:page-sequence-master is used to specify the constraints on and the order in which a given set of page-masters will be used in generating a sequence of pages. Pages are automatically generated when the fo:page-sequence-master is used in formatting an fo:page-sequence. An fo:single-page-master-reference is the simplest sub-sequence-specifier. It specifies a sub-sequence consisting of a single instance of a single page-master. It is used to specify the use of a particular page-master at a given point in the sequence of pages that would be generated using the fo:page-sequence-master that is the parent of the fo:single-page-master-reference. An fo:repeatable-page-master-reference is the next simplest sub-sequence-specifier. It specifies a sub-sequence consisting of repeated instances of a single page-master. The number of repetitions may be bounded or potentially unbounded. The fo:repeatable-page-master-alternatives formatting object is the most complex sub-sequence-specifier. It specifies a sub-sequence consisting of repeated instances of a set of alternative page-masters. The number of repetitions may be bounded or potentially unbounded. Which of the alternative page-masters is used at any point in the sequence depends on the evaluation of a condition on the use of the alternative. Typical conditions include, testing whether the page which is generated using the alternative is the first or last page in a page-sequence or is the page blank. The full set of conditions allows different page-masters to be used for the first page, for odd and even pages, for blank pages. The fo:conditional-page-master-reference is used to identify a page-master that is to be used when the conditions on its use are satisfied. This allows different page-masters to be used, for example, for even and odd pages, for the first page in a page-sequence, or for blank pages. This usage is typical in chapters of a book or report where the first page has a different layout than the rest of the chapter and the headings and footings on even and odd pages may be different as well. The fo:declarations formatting object is used to group global declarations for a stylesheet. The fo:color-profile formatting object is used to declare an ICC Color Profile for a stylesheet. The color-profile is referenced again via the name specified in the "color-profile-name" property. The fo:page-sequence formatting object is used to specify how to create a (sub-)sequence of pages within a document; for example, a chapter of a report. The content of these pages comes from flow children (consisting of the single fo:flow and any fo:static-content flow objects) of the fo:page-sequence. The layout of these pages comes from the fo:page-sequence-master or page-master referenced by the master-reference trait on the fo:page-sequence. The sequence of areas returned by each of the flow-object children of the fo:page-sequence are made descendants of the generated pages as described below. The fo:title formatting object is used to associate a title with a given page-sequence. This title may be used by an interactive User Agent to identify the pages. For example, the content of the fo:title can be formatted and displayed in a "title" window or in a "tool tip". The fo:static-content formatting object holds a sequence or a tree of formatting objects that is to be presented in a single region or repeated in like-named regions on one or more pages in the page-sequence. Its common use is for repeating or running headers and footers. The content of the fo:flow formatting object is a sequence of flow objects that provides the flowing text content that is distributed into pages. The fo:simple-page-master is used in the generation of pages and specifies the geometry of the page. The page may be subdivided into up to five regions: region-body, region-before, region-after, region-start, and region-end. Used in constructing a simple-page-master. This region specifies a viewport/reference pair that is located in the "center" of the fo:simple-page-master. The overflow trait controls how much of the underlying region-reference-area is visible; that is, whether the region-reference-area is clipped by its parent region-viewport-area. Used in constructing a simple-page-master. This region specifies a viewport/reference pair that is located on the "before" side of the page-reference-area. In lr-tb writing-mode, this region corresponds to the header region. The overflow trait controls how much of the underlying region-reference-area is visible; that is, whether the region-reference-area is clipped by its parent region-viewport-area. Used in constructing a simple-page-master. This region specifies a viewport/reference pair that is located on the "after" side of the page-reference-area. In lr-tb writing-mode, this region corresponds to the footer region. The overflow trait controls how much of the underlying region-reference-area is visible; that is, whether the region-reference-area is clipped by its parent region-viewport-area. Used in constructing a simple-page-master. This region specifies a viewport/reference pair that is located on the "start" side of the page-reference-area. In lr-tb writing-mode, this region corresponds to a left sidebar. The overflow trait controls how much of the underlying region-reference-area is visible; that is, whether the region-reference-area is clipped by its parent region-viewport-area. Used in constructing a simple-page-master. This region specifies a viewport/reference pair that is located on the "end" side of the page-reference-area. In lr-tb writing-mode, this region corresponds to a right sidebar. The overflow trait controls how much of the underlying region-reference-area is visible; that is, whether the region-reference-area is clipped by its parent region-viewport-area. The fo:marker is used in conjunction with fo:retrieve-marker to produce running headers or footers. The fo:block formatting object is commonly used for formatting paragraphs, titles, headlines, figure and table captions, etc. The fo:block-container flow object is used to generate a block-level reference-area, typically containing text blocks with a different writing-mode. In addition, it can also be used with a different reference-orientation to rotate its content. The fo:table-caption formatting object is used to contain block-level formatting objects containing the caption for the table only when using the fo:table-and-caption. The fo:table-and-caption flow object is used for formatting a table together with its caption. The fo:table-body formatting object is used to contain the content of the table body. The fo:table-footer formatting object is used to contain the content of the table footer. The fo:table-cell formatting object is used to group content to be placed in a table cell. The fo:table-row formatting object is used to group table-cells into rows; all table-cells in a table-row start in the same geometric row on the table grid. The fo:table-header formatting object is used to contain the content of the table header. The fo:table-column auxiliary formatting object specifies characteristics applicable to table cells that have the same column and span. The most important property is the "column-width" property. The fo:table flow object is used for formatting the tabular material of a table. The fo:list-block flow object is used to format a list. The fo:list-item formatting object contains the label and the body of an item in a list. The fo:list-item-label formatting object contains the content of the label of a list-item, typically used to either enumerate, identify, or adorn the list-item's body. The fo:list-item-body formatting object contains the content of the body of a list-item. The fo:bidi-override formatting object is used when the Unicode BIDI algorithm fails. It forces a string of text to be written in a specific direction. The fo:character flow object represents a character that is mapped to a glyph for presentation. It is an atomic unit to the formatter. The fo:initial-property-set auxiliary formatting object specifies formatting properties for the first line of an fo:block. The fo:external-graphic flow object is used for a graphic where the graphics data resides outside of the fo:element tree. The fo:instream-foreign-object flow object is used for an inline graphic or other "generic" object where the object data resides as descendants of the fo:instream-foreign-object, typically as an XML element subtree in a non-XSL namespace. The fo:inline formatting object is commonly used for formatting a portion of text with a background or enclosing it in a border. The fo:inline-container flow object is used to generate an inline reference-area, typically containing text blocks with a different writing-mode. The fo:leader formatting object is often used:in table-of-contents to generate sequences of "." glyphs that separate titles from page numbers;to create entry fields in fill-in-the-blank forms;to create horizontal rules for use as separators The fo:page-number formatting object is used to obtain an inline-area whose content is the page-number for the page on which the inline-area is placed. The fo:page-number-citation is used to reference the page-number for the page containing the first normal area returned by the cited formatting object. The fo:basic-link is used for representing the start resource of a simple one-directional single-target link. The object allows for traversal to the destination resource, typically by clicking on any of the containing areas. The fo:multi-toggle is typically used to establish an area that when actuated (for example implemented as "clicked"), has the effect of switching from one fo:multi-case to another. The "switch-to" property value of the fo:multi-toggle typically matches the "case-name" property value of the fo:multi-case to switch to. The fo:multi-switch wraps the specification of alternative sub-trees of formatting objects (each sub-tree being within an fo:multi-case), and controls the switching (activated via fo:multi-toggle) from one alternative to another. The fo:multi-case is used to contain (within an fo:multi-switch) each alternative sub-tree of formatting objects among which the parent fo:multi-switch will choose one to show and will hide the rest. The fo:multi-properties is used to switch between two or more property sets that are associated with a given portion of content. The fo:wrapper formatting object is used to specify inherited properties for a group of formatting objects. The fo:retrieve-marker is used in conjunction with fo:marker to produce running headers or footers. The fo:float formatting object is typically used either to cause an image to be positioned in a separate area at the beginning of a page, or to cause an image to be positioned to one side, with normal content flowing around and along-side the image. The fo:footnote is typically used to produce footnote-citations within the region-body of a page and the corresponding footnote in a separate area nearer the after-edge of the page. The fo:footnote-body is used to generate the footnote content. The following "out-of-line" formatting objects may be used anywhere where #PCDATA or %inline; are allowed (except as a descendant of any "out-of-line" formatting object): Inline-level formatting objects are most commonly used to format a portion of text or for generating rules and leaders. The following formatting objects are "neutral" containers and may be used, provided that the additional constraints listed under each formatting object are satisfied, anywhere where #PCDATA, %block;, or %inline; are allowed: The following "out-of-line" formatting objects may be used anywhere where #PCDATA, %block;, or %inline; are allowed (except as a descendant of any "out-of-line" formatting object):