This chapter introduces how to effectively organize ontology languages and ontologies and how to efficiently process semantic information based on ontologies. In this chapter we propose the hierarchies to organize ontology languages and ontologies. Based on the hierarchy of ontology languages, the ontology designers need not bear in mind which ontology language the primitives exactly come from, also we can automatically and seamlessly use the ontologies defined with different ontology languages in an integrated environment. Based on the hierarchy of ontologies, the conflicts in different ontologies are resolved, thus the semantics in different ontologies are clear without ambiguities. Also, these semanticclear ontologies can be used to efficiently process the semantic information in Semantic Web and e-business.