Footer
A large perceivable region that contains information about the application. This <footer> element contains the role='contentinfo'.
Usage
It contains information on the functioning of the site or legal information. This can include legal notices, credits, terms of use, copyright, a site map and possibly links to privacy and accessibility statements accessibility.
When to use
Be careful, this component has a 'contentinfo' role, unique in the site, and must not be confused with any other content that can be tagged in HTML5 with the <footer> element. This footer[role="contentinfo"] component is therefore reserved for the main footer and must be unique in the page (see example 'single'). However, there can be several footer tags (see example 'multiple').
Technical definition provided by WAI-ARIA: Contentinfo (role):
A large perceivable region that contains information about the parent document. Examples of information included in this region of the page are copyright and links to privacy statements. User agents SHOULD treat elements with the contentinfo role as navigational cues. In a document or application, the author should not mark more than one element with the contentinfo role.
Note
Because document and application elements can be nested in the DOM, they can have multiple contentinfo elements as descendants in the DOM, assuming that each is associated with different document nodes, either through nesting in the DOM (e.g., document within document) or through the use of the aria-owns attribute.