The Rise of Link Spam: Blame Google PageRank
http://searchengineland.com/rip-google-pagerank-retrospective-244286
Google Search has long used PageRank as part of its formula for its search engine. PageRank is a way to list a group of pages from best to worst when considering how they answer a search query. In this iterative process, each page in the network begins with an equal page rank, and then divides its page rank equally among the pages it links to. In each iteration of the process, the updated PageRank of a page is equal to the sum of the values passed to it by the pages that link to it. Pages that are have more links pointing to them have higher Page Ranks, particularly if the source pages link to only a few other pages.
While PageRank is only one part of the formula Google uses to present its search results, it is thought by many to be one of the main factors in how high a page is presented in the results. This idea developed in the early 2000s with Google’s release of the Google Toolbar for Internet Explorer. This toolbar had an option to display Google’s PageRank of any webpage, so anyone could see how “important” Google had ranked their page. While the casual internet user rarely enabled the PageRank feature, Search-Engine Optimizers (SEOs) found it a very helpful feature. With the governing idea behind PageRank being that more links equals higher PageRank, SEOs saw that they could use PageRank to find webpages that would be interested in buying links under the impression that having a higher PageRank would lead to be listed higher in Google’s results. Thus, a link-selling economy emerged as an unintended consequence of public PageRank scores. While Google took actions to curb the link-selling that undermined the natural and “democratic” nature of PageRank, the link-selling economy sidestepped, and link spam become prevalent. Link spam, the idea of dropping links into any available avenue, such as blog posts are forums, trended as another way to boost PageRank. This practice was annoying and cumbersome to those trying to use the affected sites.
Since around 2010, the fixation on PageRank has subsided as Google stopped offering support for its toolbars, and did not include the feature when it released the Google Chrome Browser. The lack of public PageView may have quelled the intensity of the link economy, but this article argues that it can never truly be stopped as long as people know that some part of Google’s formula is based on links.