Web dynpro component : It is a central control of a application, it has views, windows, controllers.
Web dynpro application : It is a URL which is associated to a web dynpro component, through which we can test a web dynpro component.
Creating hello world application in Web Dynpro ABAP.
Go to SE80, select web dynpro component/ intf from drop down, provide componenet name as ZSAPN_HELLO_WORLD, press enter a pop up will open click yes.
Provide description and enter.
Save it in a local object, save the component (Ctrl S).
Go to main view, layout, rootuielementcontainer, insert element, provide id, select page header from drop down and press enter.
Select PageHeader, and provide title in the properties area and enter.
Save (Ctrl S), double click on component name (ZSAPN_HELLO_WORLD), right click and aativate.
A pop up will open just press enter.
Now the hello world component is created, we have to execute and test this component, to test a web dynpro component we need a application...So we have to create an application for this
Again right click on component, create, Web Dynpro application.
Provide application name, description, enter and Save (Ctrl S).
Application is created, right click on application name (not component name) and test.
The out put will open in a browser...