Polyfill is a service which accepts a request for a set of browser features and returns only the polyfills that are needed by the requesting browser.
This site uses the viewport meta tag which means the content may be optimized for mobile content.
Using this tag you can set up your web app to have an application shortcut icon added to a device's homescreen, and have the app launch in full-screen "app mode".
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
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.
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
A web page. Every web page is implicitly assumed to be declared to be of type WebPage, so the various properties about that webpage, such as breadcrumb may be used. We recommend explicit declaration if these properties are specified, but if they are found outside of an itemscope, they will be assumed to be about the page
Typekit is the easiest way to use real fonts on the web. It's a subscription-based service for linking to high-quality Open Type fonts from some of the worlds best type foundries.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.