The audit of popularity consists in identifying the external links pointing towards the pages of the site to promote and to measure their contribution to the traffic of this Web site. The identification of the external links. The search for the external links is relatively simple because, for the main search engines, there is a syntax of query which allows to obtain the list of the links pointing towards the aimed site. We can remind among others the following modes of query: link:youdomainname.com on Altavista link:www.yourdomainname.com on Google link:yourdomainname.com on MSN link:yourdomainname.com on Lycos By typing link:www.google.com Google for example, we obtain a list of 3 460 000 sites pointing to Google! It is also possible to resort to free on-line services allowing to make at one time the query on several search engines and to obtain the results in a aggregated way. The Link Popularity Check service allows to identify the external links on the engines of MSN, All The Web, Fast and Altavista and proposes a service of sending the results by e-mail every month. As for the service LinkPopularity, he allows to interrogate Google, Altavista and Hotbot. This search for links can also be made through specialized types of software like Arelis which also allows to get back in an automated way the text of the identified links. It is advisable to note that these search's commands for links can only return links on sites already referenced in the indexes of the main search engines. It is possible that certain influencing sites are not in the indexes, that it is voluntary or not from their part. The number of these sites except index and their potential in term of prescription of visits is however mostly unimportant. Naturally, the search can also be made on competors domain names to identify target sites on which to obtain links and to be able to consider if the present popularity is satisfactory with regard to the similar competitors sites in their contents... Measure the contribution of the influencing sites. The count of the external links is an insufficient datum in her even, because she does not allow to distinguish the really influencing sites of the sites which bring almost no visit. The only way to measure the contribution is to analyze the audience's datas of the site towards which the external links point. All the services or stats tools parse "referrers" or URL of origin which correspond to Web pages having brought a guest by the bais of a hypertext link. For classifications on Google, potential of a site as influencer can be partially obtained by observing its Page Rank through the Google Toolbar or specialized web sites. This is however an indication among the others on the value of this site, because it is necessary to consider also the number of links proposed by this site and the context of these links.