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Action sequences that are run as system actions are powerful tools for supplying action sequences with parameters whose values don't change during the lifetime of the user's session, or the lifetime of the application. If you are a Servlet/jsp developer, you should see that this is much like the way you work with parameters in the application context and the session context of Servlets and jsps.
action Action sequences that are run as system actions in session scope are useful for caching information that is unique to an individual user. The user's full name, or the region that a manager is responsible are examples of the kind of information you may store in a session parameter. These parameters can be useful for controlling access to information in corporate databases.
Other uses for System Actions
Often an application works with lists of things, for instance a list of regions. These lists are typically used by applications to populate menus, or validate data. This data generally doesn't change during the lifetime of the application. These lists are prime candidates for creation by an action sequence that is run as system action at global scope. If you think about it, I am sure you can come up with some examples of your own!