Overview: The data analysis process requires a common understanding of the meaning of specific data. Searching, sorting and retrieving this data under a consistent view is always a challenge for geologists and engineers to obtain comparison and trend extraction. Ontologies are the semantic framework that allows bringing entities to the same semantic reference, avoiding misinterpretation of models. In this presentation, Professor Mara Abel presents several successful use cases of ontologies in the petroleum industry, explaining how this theory improves data integration and interoperability.