Google Blog: Google's index nearly doubles

Google Blog: Google's index nearly doubles: "You probably never notice the large number that appears in tiny type at the bottom of the Google home page, but I do. It's a measure of how many pages we have in our index and gives an indication of how broadly we search to find the information you're looking for. Today that number nearly doubled to more than 8 billion pages. That made me smile.
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The documents in Google's index are in dozens of file types from HTML to PDF, including PowerPoint, Flash, PostScript and JavaScript. Together these pages represent a good chunk of the world's information, but hardly all of it. That's why we keep building more advanced systems for crawling the web and creating more sophisticated indices to sort what we find. So 8 billion pages is a milestone worth noting, but it's not the end of the road. The real test is how well we do in finding what you want from within those pages. We'll keep improving that too."