Model Driven Development (MDD) provides several choices for the definition of modeling languages. The definition of a complete metamodel and the customization of a given metamodel using profiles are common approaches.
In our opinion neither of these approaches is better than the other, and the choice should depend on the characteristics of each project. This paper describes our experiences defining a graphical notation for the characterization of web navigational maps based on a MOF metamodel and a UML profile. The advantages and drawbacks of both approaches are examined, as well as the solution selected for our project.