We have seen the basic structure of an EDW GUI in the last chapter. As we have seen, the GUI is made up of elements, each of which represents a standard or custom form, or a launch point for an action (for example, an EDW program). You create custom forms when you need to link completely custom functionality to EDW's GUI catalog, but for simple search and data-entry needs the standard forms may be just enough. You augment the capabilities of standard forms by means of GUI actions a triggers. The following sections describe these objects in some detail, explains how to define them and documents the available types. The relevant section of the Advanced techniques chapter explains how to create entirely custom GUI actions and triggers.