Abstract (essential) use cases UCD technique

An abstract or essential use case is a simplified, abstract, generalized use case that captures the intentions of a user in a technology and implementation independent manner.

A fully documented essential use case is a structured narrative, expressed in the language of the application domain and of users, comprising a simplified, abstract, technology-free and implementation-independent description of one task or interaction. An essential use case is complete, meaningful, and well designed from the point-of-view of users in some role or roles in relation to a system and that embodies the purpose or intentions underlying the interaction.