While Google clearly dominates the search engine market, holding nearly 60% of market share, it is important to note that Google is not the only large internet search engine. Its main competitor, at least in the United States, is Yahoo. Part of the reason that competition even exists is that the two search engines run different algorithms, and use different criteria to rank websites. Were they both the same, Google and Yahoo would theoretically hold equal market shares, but as of 2009 Google has seemed to take a dominant position in the search engine battle.
Central to Google’s ranking system is its examination of network structure and subsequent ranking of pages with hub and list scores. This is one of the key differences between it and Yahoo. Yahoo’s search engine relies more on content of the sites, rather than where the pages connect to and from. While this may seem like a more logical approach to searching, consider that the main way to determine a websites content is by scanning it for keyword density. Yahoo evaluates page content by searching for the entered terms as well as their synonyms. In addition to this, Yahoo examines meta tags, which are a sort of identifier coded into the web page. They are one of the few search engines who scan meta tags, and they examine them for keyword inclusion. Websites which contain high keyword density as well as keywords within their meta tags often do well in terms of Yahoo rankings.
Now consider these two forms of rankings from a web page designer’s point of view. Examining the basics of their ranking system, it is much easier to optimize a page to rank highly for Yahoo than it is for Google. A page with the capacity to rank highly in Yahoo’s system need only be rich in contextual use of the keyword, while a high-ranking Google page must be “confirmed”, in a sense, by the pages that link to it. While it is important to note that Google’s network structure examination is not without flaw, Yahoo’s is much easier to manipulate. Its entirely possible, as noted in class, for a completely unrelated website, such as Amazon, to earn a high Google page rating due to its numerous links to and from a wide array of websites. It is not easy, however, for a page designer to dictate how many people and who point to their site. While the designer can place a high number of outgoing links, it is Google’s reliance on both outgoing and incoming links that make it’s algorithms more difficult to manipulate. It should be noted that though Yahoo’s method of scrutiny is easier to manipulate than Google’s it is by no means a walk in the park.
The difference between Google’s and Yahoo’s ranking criteria might indicate some of the reason why Google has been inching away from its competition for the past few years. With Google’s algorithms being inherently more difficult to manipulate than Yahoo’s, its logical to conclude that Google can produce more trustworthy results. This means that more people will likely turn to Google over Yahoo when making searches, as they do not want to find sites that could have potentially manipulated their way to the top (or near-top) of the list.

Yahoo’s Ranking Criteria
Search Engine Market Share Data