U
Unified Modeling Language (UML):

A graphical language for the modeling and development of software systems.

use case:

A UML concept used in use case modeling. A use case encapsulates a sequence of steps performed by the system on behalf of an actor.

use case diagram:

Part of the UML. Use case diagrams capture the precise requirements for the system from a user's perspective.

use case realization:

A use case realization captures how a specific use case is implemented within the system.

Get Developing Enterprise Java Applications with J2EE™ and UML now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.