When it comes to designing software, there are various modeling diagrams that software developers use to relate the software requirements to the overall design of the system. Any kind of system, whether simple or complex, is best illustrated through these different types of UML diagrams. UML stands for Unified Modeling Language and it is a developmental and modeling language used in the world of software development. UML diagrams help developers and their customers better understand how the system works in a simpler way.
Fortunately, developers have a variety of UML diagrams to choose from:
Class Diagram: Class diagrams represent the classes of the system and its objects and its methods. It is the most commonly used diagram in system design and they can consist of classes, interfaces, and associations.
Sequence Diagram: Sequence diagrams show the interaction between components in the system. It is used to represent the the exchange of data or sequences of calls to perform a certain function from component to component in a system.
Use Case Diagram: Use case diagrams show the relationship between users or “actors” as they are called. It is used to show different situations or “use cases” and shows the interaction between specific functionalities and the users.
Activity Diagram: Activity diagrams shows the flow between specific activities. In some activity diagrams, there are columns that are used and those columns represent modules. Each module can consist of a user or a component of the system and the diagram is used to show the flow of control between those modules and the functionality, i.e. “activities” of the system. This diagram is used to best represent how the system will work when it is running and working.