Use Cases

 We hear the voice of the customer, capturing the true application needs and documenting use cases. This is the foundation for ensuring usability and the foundation for creating your Product Requirements Document (PRD). Creation of use cases follows establishing a business case for the product, establishing the project charter, defining project scope and documenting the overall requirements for the new product.  

At Solid Design, we document use cases for each potential way the product could be used, describing the series of user steps making up the use case. The envisioned (required) way the system/product responds to the steps completed by the user is documented in the use case. Each use case will have the following elements:

• Name of the Use Case.
• Control code assigned.
• Description of what the user is going to accomplish with the product. This could also be a description of a fail-safe mode of operation when the product is used incorrectly or when something in the user environment changes during use of the product.
• Description of the Actor or Actors. Known in the Unified Modelling Language (UML), an actor can be a human user, a subsystem of the product or an external system.
• Triggering event that starts the use case
• What the product will achieve with a measurable output where possible.
• Preconditions of the user environment and the state of the system(product) prior to the start of the use case.
• Post conditions of the user environment and the state of the system(product) prior to the end of the use case.
• Process flow, step by step description of what the user does and what the product does to accomplish.
• Risks identified.

The use cases usually are contained within the product requirements document, these can also be a separate document or individual documents. The Requirement Traceability Matrix serves to identify requirements related to specific use cases.