CWI defined a formal model of components in terms of the basic object-oriented concepts of the OMEGA kernel language. More specifically, the CWI developed a representation in the OMEGA kernel model of both the internal and the external view of a component. With the external or blackbox view of a component its internal structure can be encapsulated. The external view will be simpler than the internal view and can make things possible that would be more complicated using the internal view only.