Here's a simplified diagram of the CDF Architecture:
The Dashboards.jsp page (/pentaho/Dashboards) is called by the user and provides the access to all Dashboards.
As common within the Pentaho Solutions, this framework works on a set of assumptions concerning the organization and naming of the folder structure and files: Each dashboard is defined in a separate folder and must contain two files, index.xml and template.html.The index.xml is used to identify the dashboard's name and description just as in any other folder in the Pentaho solution repository. The template.html file determines the dashboard's design.
The content layout as well as the static content are defined with regular HTML. Any kind of component can be used as a placeholder, being "div" and "span" tags the most commonly used. These information objects are defined as dashboard components.
When the user calls up a dashboard, one or multiple components will be executed from the dashboard library. Some of them will result in the executions of Action Sequences on the BI Platform. The platform returns the results and the dashboard library will send the content to be displayed in the specified tag back to the browser.