Skip link
A skip link is a hidden-by-default link at the top of a page that becomes visible when keyboard-focused, allowing keyboard and screen-reader users to bypass repetitive navigation and jump straight to the main content.
Detailed explanation
WCAG 2.0 SC 2.4.1 (Bypass Blocks) requires a mechanism to skip blocks of content repeated across pages — typically the header, navigation, and announcement bar. The dominant implementation is a "Skip to main content" link that is positioned off-screen by default and becomes visible on `:focus`.
A correctly-implemented skip link is the first focusable element on the page. When a keyboard user presses Tab on a fresh page load, the skip link receives focus and reveals itself. Pressing Enter jumps focus to the `id="main-content"` element on the page.
How this applies to Shopify stores
Most Shopify themes ship with a skip link in `theme.liquid`, but custom themes and theme customizations sometimes break it (positioning bugs, missing target ID, broken focus styles). AccessComply audits the skip link's presence, position, target, and focus styling.
Primary source: w3.org