An authoring system for building an application that has a set of graphical objects. The application is for performing several operations on several graphical objects in response to several user interaction events. The authoring system includes a graphical user interface (GUI). The GUI includes a first area for displaying different possible user interaction events. Each possible user interaction event is for associating with a graphical object of the application. The GUI also includes a second area for displaying operations for associating with user interaction events displayed in the first area. In addition, the GUI includes a third area for displaying definitions of an operation selected in the second area.