Navigation is easily managed with the <nav> element.
When more than one <nav> element exists on a page, it must include the aria-label or aria-labelledby attribute to differentiate each <nav> elements. For the main navigation of the site, the value of aria-label is commonly "Main".
When more than one navigation exists on the page, add an aria-label to differentiate the purpose of each navigation, e.g. aria-label="Main" and aria-label="On this page" for a table of contents menu.
Breadcrumbs
All pages except the homepage has breadcrumbs on websites. For single page applications, use breadcrumbs if feasible and adds meaning (improves understanding and the application supports save states).
Breadcrumbs are hierarchically ordered information architecture, whether representative of a file structure or a virtual structure. Use an ordered list to present it. Breadcrumb navigations are commonly identified with aria-label="Breadcrumb".
Horizontal menus are used for the primary navigation sections including breadcrumbs. Vertical navigations may be used for section submenus or “table of contents” lists for longer blocks of content.
A submenu follows the same pattern as the other navigations. If a navigation structure is flat, basic <a> anchor elements are sufficient. If a navigation has additional items “nested” underneath it, use an unordered list <ul> to properly associate the sibling navigation with its parent.
The Libraries' Drupal website does not support sub-items in menus.
Minimally, provide one primary “skip to main content” link on every page as the first item within the <body> element.
If the page contains an extraordinary amount of content and links, consider adding one or two more “skip” links to the primary task areas of the content. For instance, on a search results page, the “skip” links might be “skip to search results” and “skip to search box”.
The “skip” links may be used by visual or non-visual people, either with keyboards, screen readers, or other assistive technology. Because some people may be sighted, ensure the links are visible on focus. Ideally, the skip link is always visible, not only on focus.