Most MapGuide pages follow a similar processing flow. First, they create a connection with the site server using an existing session id. Then they open connections to any needed site services. The exact services required depend on the page function. For example, a page that deals with map feature data requires a feature service connection.
The MapGuide Viewer for details about sending data to the Viewer.
Once the site connection and any other service connections are open, the page can use MapGuide Web API calls to retrieve and process data. Output goes to the task pane or back to the Viewer. See