Public specification of a preferred URL for a page allows search engines to understand the original location for content.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
Twitter cards make it possible for you to attach media experiences to Tweets that link to your content.
The DOCTYPE is a required preamble for HTML5 websites.
Defines the attributes of a web app in a simple JSON file. It describes how the web app should appear on the users system and how it should launch.
The @font-face rule allows for linking to fonts that are automatically activated when needed.
This page contains tags that are specific to an HTML 5 implementation.
A way to make Web content and Web applications more accessible to people with disabilities. It especially helps with dynamic content and advanced user interface controls developed with Ajax, HTML, JavaScript, and related technologies.
The picture element provides images for different devices and is part of the HTML 5.1 specification.
This page contains HTML5 style media tags. HTML5 is the proposed next standard for HTML 4.01, XHTML 1.0 and DOM Level 2 HTML.
The defer attribute gives a hint to the browser that the script does not create any content so the browser can optionally defer interpreting the script. This can improve performance by delaying execution of scripts until after the body content is parsed and rendered.
The description attribute provides a concise explanation of the page content.
JSON-LD, or JavaScript Object Notation for Linked Data, is a method of transporting Linked Data using JSON.
Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in a markup language. Its most common application is to style web pages written in HTML