HTML and CSS Reference
The <nav> element is intended for navigation,
both within the page itself, as in the Wikipedia
table of contents, and through the rest of the
website. You can have any number of <nav>
elements on a page. On large sites, it's common
to have global navigation across the top
(in the <header> ) and local navigation in a sidebar
(in an <aside> element).
The <footer> element generally appears at the end
of a document, a section, or an article. As with
the <header> element, its content is generally
metainformation—author details, legal informa-
tion, or links to related information. But it's valid
to include <section> elements within a footer—for
example, when marking up appendixes.
The <small> element often appears within a
<footer> or <aside> element—it contains copy-
right information, legal disclaimers, and other
fine print. Note that it's not intended to make text
smaller. You may choose to style its contents
smaller than your main text, but, as with other
elements, its role is to describe its contents, not
The HTML DOCTYPE
The DOCTYPE declaration optionally appears at the start of an HTML
document. It comes from the Standard Generalized Markup Language
(SGML) that was used to define previous versions of HTML in terms of
the language syntax. The DOCTYPE serves two practical functions:
It's used by HTML validation services to determine which version
the document uses.
Browsers use the DOCTYPE to determine which rendering mode to use.