SAADOUNE, Billal2019-07-252019-07-252019http://dspace.univ-msila.dz:8080//xmlui/handle/123456789/15946The great acceleration and wonderful developments in the processing of natural languages have facilitated many things. One of the areas that benefit from this development is information retrieval systems, so that the capabilities of the search engines are increased. There is also a development in the information retrieval models. In end of this dissertation, we have developed a system of information retrieval based on the technology of the vector space model, and works to measure the similarity between documents and query.eninformation retrieval, vector space model, term frequency, term frequency weight, inverse document frequency, similarity ranking.Thesis