nav
<nav>, nav element, navigation landmarkDefinition
The element for a block of navigation links — the site’s sidebar, a breadcrumb, a table of contents, pagination — announced as a navigation landmark, usually wrapping a <ul> so the links are also a counted list
Not every group of links: a footer’s legal links or a paragraph with three links inside are not navigation. A page often has several — the sidebar, the breadcrumb, the in-page contents — and each past the first needs an aria-label (“Breadcrumb,” “On this page”) so a landmark list does not read “navigation, navigation, navigation.” This site’s sidebar is one, its breadcrumb another, and the glossary page’s table of contents a third.
A <nav> is a promise that the links inside get you somewhere in the site. Label it when there is more than one, and wrap a list so the count comes for free.