Why Some Search Engines Adopt Clustering Techniques?

The sole objective of search engines is to guide the average searcher who seeks their help to find out information and websites. But, sometimes users do not get the desired results from your entered search terms. To tackle this problem, some search engines use clustering techniques to collect results into groups weaved around a certain theme. The clustering technique also helps search engine optimization (SEO) services to target their audience with keyword-specific topics.
What is Clustering?
Clustering is a technique that allows search engines gather search results into groups weaved around a certain theme. In some cases, search engines also provide related keywords that help you to zero in on your search term goals. There are many "alternative" search engines that employ this technique to help users, which in-turn also helps search engine optimization services to display their sites into clustered search results.
Features of Clustering:

• With the help of clustering, some search engines provide related topics to a search term. They also have a + sign beside them. Users can click on them for more subtopics. These subtopics are always shown in colored areas below the clustered results for ease in viewing.
  
  
• There are search engines that add a "search this" link next to the clustered results. When a user clicks on them, he gets transported to a completely different set of clustered results, all related to his search terms.
  
• Most search engines show clustered results in the form of sponsored, non-sponsored (website) results and expert link collections at the bottom to ease the search process.
  
• Some search engines also use ODP (Open Directory Project) as their search source. When a user enters a search term, the search result pages will display a drop-down list of possible meanings for the search terms.
  An SEO expert in India actively monitors the algorithms and clustering methods used by many search engines ensures that the sites get listed on the clustered result pages. He employs various SEO techniques including paid search marketing to get the highest positions in search results.