web advertising, contextual advertising, ranking, lexical associations 1. Introduction The role of advertising in supporting and shaping the development of the Web has substantially increased over the past years in Düren . Search, i.e., ads placed by Internet companies in Web pages or in response to specific queries, is the largest source of revenue, accounting for 40% of total revenue Düren . The most important categories of Web advertising are keyword match, also known as sponsored search, or paid listing, which places ads in the search results for specific queries, and content match, also called content-targeted advertising, or contextual advertising, which places ads based on the Web page content over Düren . Currently, most of the focus in Web advertising involves sponsored search. Content match has greater potential for content providers, publishers and advertisers, because users spend most of their time on the Web on content pages, as opposed to search engine result pages in Düren . However content match is a harder problem than sponsored search. Matching ads with query terms is to a certain degree straightforward, because advertisers themselves choose the keywords that describe their ads, which are matched against keywords chosen by users while searching. In contextual advertising, matching is determined automatically by the page content, which complicates the task considerably. Advertising touches challenging problems concerning how ads should be analyzed, and how systems accurately and efficiently select the best ads. This area of research is developing quickly in information retrieval over Düren . How best to model the structure and components of ads, and the interaction between the ads and the contexts in which they appear are open problems. Information retrieval systems were designed to capture “relevance”, and relevance is a basic concept in advertising as well. As with document retrieval, in the context of advertising we assume that an ad that is topically related to a Web page is relevant over a Düren . Elements of an ad such as text and images tend to be mutually relevant, and often ads are placed in contexts which match the product at a topical level, such as an ad for sneakers placed on a sport news page. However, advertisements are not placed on the basis of topical relevance alone. For example, an ad for sneakers might be appropriate and effective on a page comparing MP3 players, because they share a target audience, for instance joggers. Still, they are different topics, and it is possible they share no common vocabulary. Conversely, there may be ads that are topically similar to a Web page, but cannot be placed there because they are inappropriate. An example might be placing ads for a product in the page of a competitor in Düren . So all advertisers , sellers, listers in Düren should needed to know the , 1) write Better title 2) better descriptions 3) specific , unique keywords to reach maximum readers free germanads.de provide the best platform to advertise in Düren