It wasn't so long ago that experienced system designers had to juggle all kinds of mismatched terminology to convey the most simple ideas to each other. A C++ developer, a telecommunications expert, and a Smalltalk programmer knowledgeable in MIS systems had virtually no way to talk to each other about their common experiences.
But the now-famous Design Patterns: Elements of Reusable Object-Oriented Software (see Resources) changed all that. Design Patterns gave developers across all the fields a shared design vocabulary. Since then, the 23 fundamental design patterns discussed in that book have become the Esperanto of the object-oriented developer community. You can now speak fluidly about Singletons, Composites, and Facades with reasonable certainty that your listener -- regardless of his or her expertise -- knows the design artifacts of which you speak.
A shift of similar magnitude occurred with the release of Core J2EE Patterns: Best Practices and Design Strategies (see Resources). In the short time since that book came out, the terms Session Facade, Service Locator, and Data Access Object have become ubiquitous among enterprise developers. Just as the first design patterns gave us a language for talking about object-oriented design, the J2EE patterns have given us a shared terminology for discussing the concepts of enterprise development.