(Collection of elements that graphically implements the behavior of an action. You can have assign and control elements, exception handlers or you can invoke other actions. The elements are linked through Connectors.)
(Implements your business logic. An action is coded in an action flow where you can use control nodes, queries, etc. An action can handle local variables, input and output arguments.)
Service Studio 6.0 Help
About Destination Tool
When defining the action flow of your action, you can redirect the flow to another screen. This behavior is implemented through a Destination element which you can drag onto your canvas from the Action Flow Toolbox.
Typically, this element is used to terminate a screen action flow, but you can also use it in a screen preparation if, by some reason, instead of displaying the current screen, you want to jump to a different screen.
Destination Properties | Action Flow Toolbox