Use Case Diagrams Explained

Use case Diagram is a Part of Unified Modelling Language diagram, use case is nothing by User Interacting with the System, what are the Actions he does with the system and steps he follows while he is interacting with the system. Use case will have the Primary Actor and secondary Actor, Primary Actor is the one who initiates the task, and secondary user will be supportive. In the use case diagram, we use different Components, System Boundary, use cases, Association, Actors, we have the Relationships in the use case diagram, Generalization, Include, extend. Example for the Generalization is Employees in the Employee List it may have associate, managers, Seniors and so on. Example of Extend is Forgot password it is not mandatory, whenever we forget the password, we use this so this is the example of extend. next is Includes, includes means whenever we require a use of another use case, the other use case supports it and both cannot exist without each other. The Importance of the Use case Diagram is, with the diagram one can easily understand what action the user does and how the system is saving the data, what are the actives there in each and everything the stakeholders can easily understand it, instead of explaining this in PPT or via anything. use case is best to explain the concept. if anything needs to add or remove, we can get ideas here by viewing the diagram. Since the diagrams are easy to understand. Example of the use case is Online General store website, there will be a customer who is the primary actor, and there will be system boundary it’s a rectangle box within which we are supposed to use use cases, starting the User Registers the website and gives the User name, Email address, password(User name and password and Email ID Includes in the Registration). Next User logs in the website with the login details and view the home screen, in the home screen he searches the items Select the Item view the details of the product and if he wants and add those items in the cart, once the items are added in the card, it will give option Buy now, once we click on Buy now there will be a different payment method listed and the payment is linked to payment gateway. All the Items are saved in the Server ( Secondary Actor) Which is a secondary actor. The payment options will be displayed, Card, cash, Net banking, once’s the payment option is selected the system will give option to view other products, if the user wants other product then he again searches for the product and follows the same procedure, once the payment is done, the app will send the Message to the user about the order conformation and the expected delivery. There will be a tracking that will tell the user where the product exactly. Like this example it will clearly explain the Online store navigation to the stakeholders. The Use case diagram sets the boundaries, explains the steps everything.