BOUREZG, Zeyneb2018-02-042018-02-042017http://dspace.univ-msila.dz:8080//xmlui/handle/123456789/2214The web has become a very frequent source for information described in different languages. The evolution of models and paradigms of knowledge representation in AI led to the notion of ontology in the 1980s. It plays a primordial role in creating the semantic web a new trend of the classic web that allows the user to access within the data available on the web in a more intelligent way. The present work consists in designing and implementing a multilingual ontology whose main task is to guide the multilingual semantic retrieval of information and consequently to improve the accuracy of the results obtained by the retrieval.enInformation retrieval, ontology, multilingual, semantic webThesis