Click through data is the information collected by the search engines when users click the results for different queries, Search engines always have an extensive log of the click through data for most of their results,

So is click through data used for search engine ranking purposes, NO, search engines dont use click through data for ranking algorithms, In other words they dont use click through data of their results to rank sites for keyword queries,

They do record the data but they use it for quality and auditing purposes, Google has been known to do extensive click through data logging when they do a algorithm update, Yahoo too tracks click through data but they use it only to determine the quality of their search engine results,
SEO Blog Team,

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