Substitution A substitution is an object in the layout that will be substituted with data when the output is rendered during runtime. To add a substitution to your StoryTeller document, you must: • Specify where the data will be rendered, either directly on a page or inline within a Story. • Specify the data that will be rendered in the output. The data can come from: – The Message, for example a field or a variable. Optionally the value can be translated via a language table file. – External content, for example a Story defined in another StoryTeller document, or an XHTML, LXF or RTF file. Note: For external content entered in the Composition Center web application, you must use a Section instead of an external content substitution, see Section. You can select to apply a filter to enable rich text for the contents of the substitution.