Google developed Instant based on the idea of searching for partial queries and providing some interactive feedback while searching. Google built demos over the years, but had never cracked the code, or the algorithm as it were, to deliver search-before-you-type results. Google's approach offers results for the most likely search given what has already been entered into the search box. You might call it predictive search.

"As you can imagine, searching even before someone types isn't easy -- which is why we are so excited today to be unveiling Google Instant," said Marissa Mayer, vice president of Search Products & User Experience at Google. "Google Instant is search-before-you-type. Instant takes what you have typed already, predicts the most likely completion and streams results in real-time for those predictions -- yielding a smarter and faster search that is interactive, predictive and powerful."

Behind the Instant Scenes

Mayer explained the technology behind Instant. She said Google needed to develop host of new technologies, such as new caching systems, the ability to adaptively control the rate at which Google show results pages, and an optimization of page-rendering JavaScript to help Web browsers keep up with the rest of the system.

Ultimately, Google was tasked with producing a system that is able to scale while searching as fast as people can type and think without compromising the relevancy of its results. Although Mayer cites many benefits of using Instant, she said the overarching advantage is a time savings.

"Our testing has shown that Google Instant saves the average searcher two to five seconds per search," Mayer said. "That may not seem like a lot at first, but it adds up. With Google Instant, we estimate that we'll save our users 11 hours with each passing second!"

Mobile Implications

Greg Sterling, principal analyst at Sterling Market Intelligence, said the feature dramatically speeds up search and makes it more interactive. What's more, he said, Instant Search eliminates some of the steps in getting to desired results. As he sees it, Instant Search will likely have an impact on user behavior and search marketing Relevant Products/Services although those impacts are a bit uncertain at the moment.

"Some are predicting the 'end of SEO.' I don't think that's true but there will be an impact on SEO," Sterling said. "For example, it appears to concentrate more attention at the very top of the search results page. While users can cycle through many more pages quickly they will look at fewer results."

Sterling sees mobile Relevant Products/Services as an arena where Instant Search could really pay off for Google, by making it easier to interact with the traditional search box. In general, Sterling said he expects most users will have a positive reaction, though some may dislike it -- in which case you can turn it off.

By Jennifer LeClaire