In Unified Modeling Language in the field of software engineering, a profile diagram operates at the metamodel level to show stereotypes as classes with the <code>ëstereotypeû</code> stereotype, and profiles as packages with the <code>ëprofileû</code> stereotype. The extension relation (solid line with closed, filled arrowhead) indicates what metamodel element a given stereotype is extending.
The profile diagram did not exist in UML 1. Other diagrams had been used to display this issue. It was introduced with UML 2 to display the usage of profiles.