We can think of the internet as the largest library in the world operating without the benefit of the Dewey Decimal Classification System. There are more websites on the internet than there are people on the earth and new sites are being added every moment of the day. There may be hundreds of thousands of pages covering the same topic. Which ones among the millions out there will have the information we seek?

Search engines are special purpose websites designed to help us find the web sites with the information we want. We are going to talk about three of them; Google, Yahoo and MSN which were 'the big 3' at the time this article was written. Each of them use different methods to provide search results in what they hope are arranged from the most to least relevant.

Google's method of ranking the relevance of results is reportedly based on the importance of websites with information about the topic you seek. How Google determines the importance of a website is a matter of much debate but in the simplest terms it is this: the more sites that link to a given site, the more important it must be. This means the results returned first are often from more established sites that have been around long enough to attract links from many other sites.

Yahoo's method of providing search results has changed several times since they began. At first inclusion in the Yahoo directory was done manually, then for a fee, then from other search engine companies and for a time they even used results directly from Google. At this time although they still slowly list sites for free, the quickest route into Yahoo search results is by paying an annual fee. It should come as no surprise then that the top results from Yahoo seem to be weighted in favor of the websites sponsored by businesses for which the annual fee is no obstacle.