The study deals with the analysis of taxonomy applications for the sites of Arab and foreign national libraries; In terms of navigation systems, taxonomic structure and research methods in order to identify the most important features of these sites and their developments, and the impact of these applications on them; To help those in charge of designing this type of websites or people who manage national libraries to classify the site in a way that leads to the greatest benefit by users, and to show the precious treasures owned by those libraries, as well as analyzing the sites of Arab national libraries and comparing them with the sites of foreign national libraries ; In order for the study to verify its proper application of taxonomy and access to the strengths and weaknesses within those sites, and to set a set of guiding controls that the study deduced through its study of foreign sites in order to help Arab library site makers for reference when preparing navigation and search systems; This is because there are no unified Arab or foreign standards that can be referenced when creating this type of site, as the success of any site in use by the beneficiaries depends on the efficiency of its classification structure.