Anti-bot CAPTCHA widget that helps digitize books by providing snippets of books for people to enter the text for. Owned by Google.
CloudFlare is a global CDN and DNS provider that can speed up and protect any site online.
This site uses the viewport meta tag which means the content may be optimized for mobile content.
Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
A rich hosted Exchange environment for every user without having to manage a server.
Open graph description entity tag
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook