HTML
Diverse
https://www.w3.org/wiki/HTML/Elements/link
http://www.w3schools.com/tags/tag_link.asp
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/link
https://mathiasbynens.be/notes/rel-shortcut-icon
https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-charset
https://code.google.com/p/doctype-mirror/wiki/MetaCharsetAttribute
http://stackoverflow.com/questions/4696499/meta-charset-utf-8-vs-meta-http-equiv-content-type
https://gtmetrix.com/specify-a-character-set-early.html
HTML <html> xmlns Attribute
A simple XHTML document, with the minimum of required tags:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Title of the document</title>
</head>
<body>
The content of the document......
</body>
</html>
HTML <!DOCTYPE> Declaration
Recommended list of Doctype declarations (DTD:s)
https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/lang
https://www.htmlgoodies.com/html5/7-ways-to-get-the-most-out-of-html5.html
Styling HTML forms
HTML5 Progress Element
Cross Browser HTML5 Progress Bars In Depth
<input type="range">
submit
https://developer.mozilla.org/en-US/docs/Learn/Accessibility/WAI-ARIA_basics
https://webaim.org/techniques/screenreader/
https://webaim.org/techniques/semanticstructure/
https://webaim.org/techniques/skipnav/
w3.org / Web Hypertext Application Technology Working Group (WHATWG)
Namespaces
HTML 5.1 - Namespaces (www.w3.org)
Infra - Namespaces (infra.spec.whatwg.org)
HTML 5 - Namespaces (dev.w3.org)
Namespaces in XML (www.w3.org)
Understanding XML Namespaces (MSDN)
Namespaces (MDN)
The HTML namespace is: http://www.w3.org/1999/xhtml
The MathML namespace is: http://www.w3.org/1998/Math/MathML
The SVG namespace is: http://www.w3.org/2000/svg
The XLink namespace is: http://www.w3.org/1999/xlink
The XML namespace is: http://www.w3.org/XML/1998/namespace
The XMLNS namespace is: http://www.w3.org/2000/xmlns/