Use Cases

TechTarget Network describes use case as:

... a methodology used in system analysis to identify, clarify, and organize system requirements. The use case is made up of a set of possible sequences of interactions between systems and users in a particular environment and related to a particular goal. It consists of a group of elements (for example, classes and interfaces) that can be used together in a way that will have an effect larger than the sum of the separate elements combined. The use case should contain all system activities that have significance to the users. A use case can be thought of as a collection of possible scenarios related to a particular goal, indeed, the use case and goal are sometimes considered to be synonymous.

For all its functionality, there does not seem to be one way of writing use cases. In their paper The art of writing use cases, presented at the Conference on Object-Oriented Programming, System, Languages, and Applications in Minneapolis, 2000, Wirfs-Brock and Scwartz identified three forms of use cases:

• Narrative Form
• Scenario Form
• Conversation Form

These three forms will be used to classify the use cases that were collected for this project. A fourth form, Larry Constantine’s essential use cases, will also be used.