Treating accessibility as a core engineering practice, not an afterthought, benefits the 15% of the global population with disabilities and improves usability for all. Legal requirements like WCAG compliance make it non-negotiable for many organizations, while features like captions and high contrast aid everyone in challenging environments.

The foundation is proper semantic HTML. Most issues arise from misusing elements, like building buttons from divs or links from spans. Using correct headings in order, associating form labels with inputs, and avoiding placeholders as labels ensures screen readers can interpret the page structure accurately.

Keyboard navigation is critical; users must reach every interactive element without a mouse, with clear focus indicators and logical tab order. For screen readers, meaningful alt text for images is essential, and ARIA labels should be a last resort when semantic HTML falls short. Testing requires real user feedback alongside tools like Lighthouse and axe-core.