http://www.smartdraw.com/tutorials/software/uml/tutorial_01.htm
SmartDraw UML Center
HOW TO DRAW UML DIAGRAMS
What is UML?
UML stands for Unified Modeling Language. This object-oriented system of notation has evolved from the work of Grady Booch, James Rumbaugh, Ivar Jacobson, and the Rational Software Corporation. These renowned computer scientists fused their respective technologies into a single, standardized model. Today, UML is accepted by the Object Management Group (OMG) as the standard for modeling object oriented programs.
Types of UML Diagrams
UML defines nine types of diagrams: class (package), object, use case, sequence, collaboration, statechart, activity, component, and deployment.
Class Diagrams
Class diagrams are the backbone of almost every object oriented method, including UML. They describe the static structure of a system.
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