Ontology is one of the central area in natural language processing (NLP), artificial intelligence (AI) information retrieval (IR) and semantic web (SW). If you are working on ontology project, this paper will give you the relevant information about ontology related terms and best ontology development editor. In this paper five ontology development editors are reviewed and compared with their updated versions. They are Apollo1.0, SWOOP 2.3Beta4, Protégé 5.0, Graffoo 1.0 and Neon 2.5.2. Comparison of two main data models ontology and RDBMS is also done. This paper also present the classification of ontology languages from those reported in the Literature, with a special attention accorded to the interoperability between them. Additionally, this paper presents the important terms related to ontology. The main criterion for comparison of these tools and languages was the user interest and their application in different kind of real world tasks. The primary goal of this study is to introduce these important tools, languages and data models to ensure more understanding from their use.