You use the system context diagram to set the context of a system in your enterprise that you are modeling. You place one System symbol on the diagram, model the externals and data that the system interfaces with, and generally create one or more child diagrams to show more detail about the system.

You can use the diagram to model existing or future systems and their interfaces -- the scope of the system is that of a single release of a single product.

The following information describes the basic symbols of the system context diagram:

The diagram's single System Symbol has the same name as the System and release. The scope of the System Symbol includes all processes of the system.

External symbols are outside the scope of the System but interface with it. The External could be another company, agency, or system.

Data Flows are external interfaces between the External and the Application.

A Data Store symbol is where data "rests" when it is neither flowing nor being operated on. A data store can be a database, hard disk or a file on a disk.