HTML Accessibility & ARIA
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Expert Answer & Key Takeaways
Mastering HTML Accessibility & ARIA is essential for high-fidelity technical architecture and senior engineering roles in 2026.
Introduction to a11y
Web accessibility (often abbreviated as a11y) means that websites are designed and developed so that people with disabilities can use them. This includes users who rely on screen readers, keyboard-only navigation, or voice commands.
<!-- Poor Accessibility -->
<div onclick="submit()">Click Me</div>
<!-- Good Accessibility -->
<button type="button" onclick="submit()">Click Me</button>ARIA Roles & Attributes
ARIA (Accessible Rich Internet Applications) is a set of attributes that help explain the purpose of elements to screen readers when semantic HTML isn't enough.
role: Defines what the element is (e.g.,role="button",role="alert").aria-label: Provides a text label when there is no visible text.aria-hidden: Hides decorative elements from screen readers.
<button aria-label="Close" onclick="closeModal()">X</button>HTML Landmarks
Landmarks help users navigate the page using screen reader shortcuts. Using semantic tags automatically creates these landmarks:
<header>: The header landmark.<main>: The main content landmark.<nav>: The navigation landmark.<footer>: The footer landmark.
If you must use a
<div>, you can add a role: <div role="navigation">.Keyboard Accessibility & Tabindex
Users who cannot use a mouse rely on the
Tab key to navigate.- Tabindex="0": Makes an element focusable in the normal sequence.
- Tabindex="-1": Makes an element focusable only via script (removes from tab order).
<div tabindex="0">Focusable via keyboard</div>💡 Interactive Task
Try navigating your favorite website using only the
Tab key and Enter. Can you reach every link? If not, the site has poor accessibility!Interview Corner
❓ Interview Question
Q: What are ARIA roles and when should they be used?
A: ARIA roles provide extra semantic information to screen readers. They should be used only when standard HTML tags (like
<nav> or <button>) cannot convey the function of an element.❓ Interview Question
Q: Why is the semantic heading hierarchy (h1-h6) important for accessibility?
A: Screen reader users often navigate pages by jumping from heading to heading. A logical order (h1 -> h2 -> h3) creates a clear table of contents for them.
❓ Interview Question
Q: What is a 'Focus Trap'?
A: A focus trap occurs when a user's keyboard focus gets stuck inside an element (like a modal) and they cannot navigate back to the rest of the page. Good accessibility ensures focus is managed correctly.
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