Anti-bot CAPTCHA widget that helps digitize books by providing snippets of books for people to enter the text for. Owned by Google.
Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
CloudFlare is a global CDN and DNS provider that can speed up and protect any site online.
Google's hosted library for web fonts. Allows websites to choose and use fonts from a free, wide variety of fonts.
Sites who has this tag are verfied by google to use WebMaster tools
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook