And Now for the Relevance to Software…
Now is the time to summarize that we have seen how progress is made in all fields by having a common notation that can be used to express concepts, and how diagrams begin to take on precision and meaning once we attach semantics to the pictures. The most useful of these notations are understood the world over.
But before 1996, there was no common notation for software. Before the UML became an international standard, two software engineers, even if they spoke the same language, had no way to talk about their software. There were no conventions that were universally accepted around the world for describing software. No wonder progress was slow!
With the advent of the UML, however, software engineers have a common graphic vocabulary for talking about software. They can draw progressively complex diagrams to represent their software, just the way electrical engineers can draw progressively complex diagrams to represent their circuits. Things like nested diagrams become possible, so different levels of abstraction can now be expressed.
Rational Software's contribution in this area was huge. Formulating the UML and bringing the world's most influential companiesIBM, Microsoft, HP, Oracle, and othersto agree on it was a major step. Getting an international standards bodythe Object Management Groupto ratify it as a standard was the formal process that irreversibly cast the die. Everyone agreed to end the Tower of Babel approach and also agreed about how to talk about software.
The significance of the UML is now established, and we can move on.