It’s pretty clear that Google doesn’t subscribe to the philosophy of “if it ain’t broke, don’t fix it.” The company is currently working on a massive, yet subtle, overhaul of its search engine technology. The code name for the project is Google Caffeine, and you can start using a preview version of it right now.

If you click that link, you’ll see a search engine page that looks amazingly similar to the current Google page. In fact, it will look identical apart from the URL. That’s because the Google Caffeine project isn’t about updating Google’s user interface. Instead, the company is trying out new ways to index Web sites and organize them for searches.

Google developer Matt Cutts blogged about the project on Monday. Cutts explains that casual users won’t really notice a difference in their search results and even power users may find differences to be hard to spot. Cutts points out that search results will change but it may take an eagle eye to notice it.

What does a change in indexing mean to the average user? It really means that Google will start to pull search results from newer Web pages much more quickly than before. In order for a search engine to display a result, it must first analyze and index the Web page. This takes time — thousands of pages of content go live on the Web every minute. But what if a brand new Web page has exactly the information you need? If the search engine hasn’t indexed that particular page yet, you may never see that data.

The new indexing approach might help Google keep up with new content. Other search engines already have this capability — Twitter Search lets you search for terms in recent tweets and even alerts you to new results that post after you’ve already performed your search. The challenge for Google is to incorporate new pages and rank them appropriately so that your search results aren’t dominated by the most recent content on the Web. Google wants to serve up the best results to users — sometimes that’s not the most recent content.

You might think that Caffeine is a response to other developments like Microsoft and Yahoo’s partnership deal or the unveiling of Microsoft Bing. But the fact is that developing such a huge endeavor requires months of planning and engineering — Google Caffeine has been in the works for a while now. Cutts also points out that the summer is a good time to test new technology — fewer people are online in the summer than in other parts of the year and Google can spare servers to test the technology without affecting the user experience.

Learn more about Google at HowStuffWorks.com:

How Google Works
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