When you create models and their corresponding diagrams, you can define both real names and aliases for each of the elements. The real name is the name of the UML element that is displayed in the Project Explorer view and is used when you generate code. The alias is an alternative name that is displayed in the diagrams. Aliases are useful when you generate code from a model and want a diagram element to have a name that is different from the name in the Project Explorer view.
Aliases are useful when you want to present the information in the diagrams in a way that makes sense to the stakeholders or reviewers. For example, if the author of a model must present it to several Japanese-speaking analysts, she can specify a Japanese alias for each diagram element so that the diagrams are more meaningful to the analysts.
Aliases do not affect any transformations that you run because they are
not the real UML element names.