HTML and CSS Reference
3.7. The Document Header
The document header describes the various properties of the document,
including its title, position within the Web, and relationship with other
documents. Most of the data contained within the document header is
never actually rendered as content visible to the user.
3.7.1. The <head> Tag
The <head> tag serves to encapsulate other header tags. Place it at the
beginning of your document, just after the <html> tag and before the
<body> or <frameset> tag. Both the <head> tag and its corresponding end
</head> tag can be unambiguously inferred by the browser and so can be
safely omitted from an HTML, but not from an XHTML, document. We en-
courage you to include them in all your documents, since they promote
readability and support document automation.