A Use case diagrams describes the interactions between the system you are building and the external world. In use case diagrams, this users external to the system are represented by actors. Actors could be actual people, device, hardware or other systems with which interact with the system. In all cases, a use case represents the steps/actions that the actor will take to get a benefit from the interaction with your system. You can then use these steps to start modeling how this will be represented in your system, typically at first as class, sequence, or activity diagrams. You can draw use case diagram with a UML modeling tool.
The figure below shows a use case diagram example.
A data flow diagram (DFD) explains the relationship among different components of a system by showing the flow of data within it. On the other hand, use case diagram is a behavioral UML diagram type and frequently used to analyze various systems. They enable you to visualize the different types of roles in a system and how those roles interact with the system. You can draw use case diagram online with Creately online diagramming and collaboration software.
ReplyDeleteExactly what I was looking for. The diagram help a lot. Thanks. I will need more materials on this topic by relating it to Payroll system design
ReplyDeleteWhen comparing data flow diagrams and use cases, what do data flow diagrams show that use case diagrams have a difficult time trying to explain?
ReplyDeleteusecase diagrams do not include data stores,DFDs do.
ReplyDelete