The Use tag is an extremely powerful feature in Iron Speed Designer. The GEN:Use tag allows you to include other reusable components on a page. The reusable components allow you to use common components across multiple pages. Changing the component once will change all of the pages that use this component.
For example, you can create a menu that is common across the entire application and reuse this menu component on each page by including or “using” the component on the page. Similarly, the header and footer on each page can be created as components and each page can refer to them in its own layout.
For complete details, see “Building Reusable Panels and Components”.
Use Pass-Through Attribute Properties