The system architecture defines how the application interacts with other applications. Not necessarily how the application itself works but, how the appropriate data is correctly passed between applications.

The system architecture provides an overview of how the functionality and responsibilities of the system were partitioned and then assigned to subsystems or components.

At the top$-$most level, the system architecture describes the major responsibilities that the software must undertake and the various roles that the system $($or portion of the system$)$ must play. It describes how the system was broken down into its components$/$subsystems $($identifying each top$-$level component$/$subsystem and the roles$/$responsibilities assigned to it$).$

The system architecture also describes how the higher$-$level components collaborate with each other in order to achieve the required results.

Using any software tool of your choice $($e$.$g$.,$ Visio, PowerPoint, MS Word, yED, Lucidchart, etc.$)$ create, draw and submit...

The system architecture design for a library patron system.