You might have noticed that Google and Yahoo show different results when you search, but why? The simple answer is that each search engine uses different methods to decide what’s relevant to you, and also what sites they want you to see, for advertising reasons.
Search engines have a lot of different ways to decide what to show you. Among them are reading the page title, headings, the text, image names, the web site name, information you can’t see (in the behind-the-scenes coding) and also how many pages are linked to each site.
The first thing to keep in mind is these are both big, wealthy sites who make money from advertising. Fortunately Yahoo and Google will return free results alongside the paid ads, but they still have some big differences in what comes up.
Each engine places different values on what matters the most. If we look closer here are the main differences from Google to Yahoo:
Google looks closely at a web page’s text and also where it links to. It can tell a little better if the links make sense, and manages to filter out a lot of sites that have added fake or broken links just to try to get themselves on top of the search results.
Lots and lots of links to different sites need to be relevant – if they are links to unrelated sites Google won’t rank it as highly as a page full of relevant links.
Yahoo will often include a page filled and overflowing with one particular word – again which the owner has repeated over and over to try to get themselves up to the top of the search results. Google realises that it’s probably not the best article if it needs this to get there, and will sometimes remove it from the results shown to you.
Yahoo isn’t quite so good at stopping "clone" sites appearing more than once. Ten sites all saying the same exact text isn’t very useful to you, and Google tends to keep these out a bit better.
Overall, Google tends to supply general information results, and Yahoo’s results tend to be a little towards the shopping side of things – even if those results aren’t paid advertising for Yahoo.
So there you have it. There are technical scientific reasons of course, but the search engines guard these fiercely from our eyes. Which one you use comes down to personal preference. I prefer Google as it feels a little less biased, but a true shopaholic will love Yahoo. So enjoy whichever one suits you best.