225 Copyright © 2010, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 10 From Temporal Databases to Ontology Versioning: An Approach for Ontology Evolution Najla Sassi MIRACL Laboratory, Tunisia Zouhaier Brahmia MIRACL Laboratory, Tunisia Wassim Jaziri MIRACL Laboratory, Tunisia Rafk Bouaziz MIRACL Laboratory, Tunisia INTRODUCTION In computer science, several application areas are especially concerned with versioning such as software development, CAD/CAM applications, temporal databases and ontologies. Temporal databases support time-varying infor- mation and maintain the history of the modelled data (Jensen et al., 1998) (Özsoyoğlu et al., 1995) (Tansel et al., 1993). Versions of temporal data are kept along one or two time dimensions: valid time and transaction time (Jensen et al., 1998). The valid time concerns the time of the modelled real world and denotes the time a fact was, or will be true, whereas the transaction time is the one of the system and concerns the one during which the fact was or is current in the database as a stored data. AbsTRACT The problem of versioning is present in several application areas, such as temporal databases, real-time computing and ontologies. This problem is generally defned as managing changes in a timely manner without loss of existing data. However, ontology versioning is more complicated than versioning in data- base because of the usage and content of ontology which incorporates semantic aspects. Consequently, ontology data models are much richer than those of database schemas. In this chapter, the authors are interested in developing an ontology versioning system to express, apply and implement changes on the ontology. DOI: 10.4018/978-1-61520-859-3.ch010