Use cases are used to organize system requirements and models a system/actor interaction, this interaction must achieve a goal. The actor is not limited to humans, it can also be a system. Use cases are often used to describe the goals of the different stakeholders involved with the project. In other words, they are used to represent how the real world interacts with the system.
Use cases are important because it acts as a summary of what the system offers. They also help in defining roles and the actions that each role can take within the system. They define a user’s needs and can prevent problems that would otherwise arise if development starts with less planning.
In order to create use cases, there are a couple of steps that need to be done:
- Identifying the users.
- Create user profiles, which include the role of each user.
- Associate goals with the roles.
- Define a use case for each one of the goals.
- Structure the use cases.
- Review the work done.
One easy way to show use cases is through the use of a use case diagram. The diagram shows the different roles, the goals, the associations between roles and goals, and the system itself. The diagram makes use cases easier to understand.
With use cases you can see an overview of the system and how users will interact with it. It’s a useful tool to use before development starts to eliminate and possible confusion.
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