As already mentioned in Section 2 modules are the structural unit of Milord II. A Knowledge Base consists of a set of modules, with each module containing submodules, and submodules containing subsubmodules, ... defining a hierarchy. There are two types of modules: plain modules, as explained in Section 2, and generic modules, that are to be considered as functions between plain modules. That is, given one, or more, modules as argument a generic module gives a plain module as result. To complete the picture of the modular language component a set of operations between modules is provided.