In UML models, a custom UML profile is a package that contains stereotypes and constraints that adapt the UML metamodel for a particular domain. A custom profile extends UML without changing the base metamodel. UML 2.0 provides a standard set of profiles. You can create a custom UML profile, if the standard UML 2.0 profiles do not meet your requirements.
A custom UML profile is helpful in the following situations:
A custom UML profile is stored in a profile model. A profile model has the file name extension .epx and is displayed in the Model Explorer view. You can create a profile in an existing project or you can create a profile project that contains the EPX file. The version number of a profile increments when you save the profile.