Case · WebGlossary.info

In engineering, as use case, a list of actions or event steps typically defining the interactions between a role (known in UML as an actor) and a system to achieve a goal. The actor can be a human or other external system. In systems engineering, use cases are used at a higher level than within software engineering, often representing missions or stakeholder goals. ← Wikipedia
In programming, a selection mechanism to allow a variable to change the flow of a program. ← Wikipedia
In typography, as letter case, the distinction between the letters that are in larger upper case (also uppercase, capital letters, capitals, caps, large letters, or more formally majuscule) and smaller lower case (also lowercase, small letters, or more formally minuscule) in the written representation of certain languages. ← Wikipedia