Websites using some form of Captcha technology on them.
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.
The Apache HTTP Server is an open-source HTTP server for modern operating systems including UNIX, Microsoft Windows, Mac OS/X and Netware. The goal of this project is to provide a secure, efficient and extensible server that provides HTTP services observing the current HTTP standards. Apache has been the most popular web server ...
Phusion Passenger - a.k.a. mod_rails or mod_rack - is a web server and application server, designed to be fast, robust and lightweight. Administration tools allow you to gain insight into web application operations and server performance.
Ruby on Rails is an open-source web framework that is optimized for programmer happiness and sustainable productivity. It lets you write beautiful code by favoring convention over configuration.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
Sites who has this tag are verfied by google to use WebMaster tools
Chrome for Android, since version 39 supports the "theme-color" meta tag to allow websites control the background color of the tab's UI header.