Anti-bot CAPTCHA widget that helps digitize books by providing snippets of books for people to enter the text for. Owned by Google.
This site uses the viewport meta tag which means the content may be optimized for mobile content.
CloudFlare is a global CDN and DNS provider that can speed up and protect any site online.
nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
Meta descriptions are HTML attributes that provide concise explanations of the contents of web pages. Meta descriptions are commonly used on search engine result pages (SERPs) to display preview snippets for a given page.
Sites who has this tag are verfied by google to use WebMaster tools