IRIS 42: Information and Research Instruction Suite for two-year colleges

Why is That Site Listed First?

Google's Ranking System

Google retrieves websites based on a system they developed called PageRank.  PageRank works in part like a ballot, where a hyperlink to a web page counts as a vote of support. A web page that is linked to by many other pages with a high PageRank receives a high rank itself. (More in-depth explanation of PageRank.)

There are pros and cons to this system. The most notable drawback is the higher a page is ranked, the more it will be visited and linked to, which keeps it high on the list.

The best example of this drawback can be demonstrated by searching for "martin luther king jr". If you're expecting to find reliable sites about Dr. King, you might be surprised to find that one of the sites on the first page is, a "hate" site from a white supremacist group. One of the reasons this page is ranked so high is that librarians and teachers continue to link to it and use it as an example of why you can't always trust results on the first page. (Notice there is no link to that site in this example!)

The lesson to remember: Popularity does not guarantee quality or reliability. Regardless of how high a web site might be in your list of results, always take the time to critique and evaluate it for credibility, accuracy, and relevance. Next >>