The abstract user interface tree is the XML representation of the application forms displayed to the end user.
The abstract user interface tree (AUI tree) is a DOM tree describing the objects of the user interface elements of a program at a given time.
A copy of the AUI tree is held by both the front end and the runtime system.
AUI tree synchronization is automatically done by the runtime system using the front end protocol.
The programs can manipulate the AUI tree element by using XML utility classes or high-level built-in classes such as ui.Dialog and ui.Form.