The Konami Code is a "cheat code" that appeared in many of Konami's video games going all the way back to 1986. Konami JS allows websites to add their own easter to be triggered by their users by entering the Konami code key press sequence: "up, up, down, down, left, right, left, right, B, A".
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.
Indicates that the site provides an interface specifically for searching the document and its related resources.
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