The perceived expertise level of a Web site, as measured by its network of inbound hypertext links. Search engines typically place great importance on sites that have many inbound links from other well-linked sites, and place those sites at the top of search results for queries on subjects that match the site’s subjects.
An analysis by search engines to determine the authority or ranking of Web pages by examining the network of connections between Web pages. Search engines use link analysis when ranking search results by relevance—pages that have many inbound links from high-authority pages are ranked higher than other pages in the search results.
The accuracy with which an organic search match is closely related to the query. A match with very high relevance will be ranked higher. Search engines sort the matches by relevance using a ranking algorithm. The algorithms use many increasingly sophisticated factors, including the location of the keywords on the matching web pages, the authority of the page, the anchor text of inbound links, the keyword density, presence of related keywords, proximity of different keywords.