At a high level, use case represents the general phrase or explanation for addressing a challenge through a set of tasks. At a deeper level, it encompasses set of possible sequences of interactions between systems and users in a particular environment to overcome the challenge.
What is a Use Case?
In a classical sense of UML (Unified Modelling Language), a use case represents a detailed sequence depicting how a systems should behave in various real-world situations,nand is an important component of any system’s design specifications. This is elaborated in a technical interpretation covering the description of how an actor interacts with a system, and how the system behaves within a scenario to achieve a set of objectives for the user. Here the system may refers to a technology platform, hardware device, or a software tool. Actor may refer to a human user or another system. Scenario refers to a real-world problem, and the objectives define a solution to the problem. This is a standardized way to represent a use case as per UML specifications.
However in colloquial terms, use case is widely represented informally in three ways, such as
- An idea keyword that centers around overcoming a specific challenge, for example, “securing website”, or “classifying animal pictures”.
- A common phrase or theme representing an ubiquitous obstacle, for example, “customer segmentation”, or “passwordless authentication”.
- A brief description of a problem, for example, “converting speech to text with language translation”.
Additionally, a lot of times in everyday conversation, people also say “Here’s a use case for this tool,” to mean that the tool can help overcome the challenge/obstacle/problem for the users. In this case, the technical nuances are encapsulated within the tool, so that the users can transition form the problem to solution without breaking sweat.
Formalization of Use Cases
Use case is a powerful concept to solve real-word problems. However, it is an intangible concept and due to different interpretations, it’s applicability is vague.
To apply an use case for a real-world situation, it is important to formalize it through four stages:
- Idea: in this stage the user case merely represents a challenge statement and supporting narrative around the challenge and the possible ways to overcome it.
- Business case: In this stage , the idea is expanded to build a three part narrative, around the problem statement, realization approach and solution space, with a focus on a business scenario or a real-world application.
- Technical realization: This stage consists of evaluating and finding the best alternative to transition from the problem statement to the solution space. It is succeeded by the actual technical description of the use case, which is close to the standardized UML representation as mentioned earlier. At the end of this stage, the use case takes the shape of a blueprint or design artifact to solve the problem.
- Implementation: This is the phase where the actual technical implementation is carried out to address the challenge / problem by means of a combination of software, hardware, mechanical, or any other applicable technology interventions. The end result is a proof-of-concept or a minimum viable product.
During the four phases, the use case progressively transitions form an intangible concept to a tangible product or service that is geared to overcome the initial challenge statement.