Use cases and user stories are two popular ways to capture functional requirements. They’re both goal-oriented and can be discovered during workshops, can be easily combined with the user experience activities, and are used in Agile Scrum.
The difference between use case and user story are as follows :
- A user story is a brief description of functionality as viewed by the user’s role, it does n’t show the interaction between the actor and the system, what the use case does. A user story is not a sequence of actions.
- A user story is short and concise which written in the language of the user and the format is “As a [role], I want to [perform an activity] so that [a goal is achieved]”. For Example, As a new user, I want to register so that I can book a flight. A role is defined and the goal which is to achieve is taken. A use case is heavier, more detailed in information, as the template of use case shows the goal, summary, actor, precondition, postcondition, trigger event, and extensions (alternative paths, errors, etc).
- A user story is smaller and can finally be seen as a part of a specific use case which is the bigger story or task.
- User stories are used for planning as they play a major role in project estimation and planning using story points and velocity. Use cases are not used for planning.
- User stories emerge faster than use cases because it is based on role and goal wherein use cases require more time for analysis and writing as it describes everything to achieve the major goal.
- User stories are more readable than use cases because it is only focused on who needs it and why it is required, wherein use cases usually belong to a large word document which discusses the goal in a more detailed way.
- User stories are based on verbal communication and rely on collaboration, discussion, and proximity to clarify details. The use case is a textual model which is supported by diagrams.
- User stories are in theory written on cards, the 3 C rule: Card, Conversation, Confirmation, they’re not intended to be archived, unlike use cases.