Summary  
This chapter explains how to implement accessibility features—adding text alternatives for images, captions for videos, and ensuring sufficient color contrast via HTML and CSS—to make content perceivable by all users.  

General domain of usage  
Web development

The first principle of web accessibility, **Perceivable**, is about making sure that all users can detect and understand the information presented on a website. This means that nothing should be invisible to anyone, regardless of their abilities or the technology they use. To achieve this, you need to provide **text alternatives** for non-text content, such as images, so that screen readers and other assistive technologies can convey the information to users who cannot see the visuals. **Captions** for videos are also essential, as they allow users who are deaf or hard of hearing to access audio content. Another key aspect is ensuring sufficient **color contrast** between text and its background, which makes content readable for users with low vision or color blindness.

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Which of the following helps make web content perceivable?

Why is color contrast important for accessibility?

Gain a clear understanding of the principles, standards, and legal frameworks that make the web accessible to all users. Explore global guidelines like WCAG and WAI ARIA, learn how assistive technologies interpret digital content, and identify common barriers that affect real users. Build the skills needed to evaluate and improve accessibility, creating digital experiences that are inclusive, compliant, and usable across diverse contexts.

Explore what web accessibility means and why it matters. Understand who benefits from inclusive design, how it impacts users and society, and what legal responsibilities guide accessible development.

Discover the foundational POUR principles—Perceivable, Operable, Understandable, and Robust—and learn how they guide accessible web design. Identify common barriers and practical ways to remove them.

Examine the key international frameworks that define accessibility standards. Understand WCAG guidelines, conformance levels, and the role of WAI ARIA and global legal policies in ensuring compliance.

Understand how assistive technologies interact with web content and support diverse user needs. Explore how thoughtful design and real user testing lead to more inclusive digital experiences.

Assess websites for accessibility and interpret audit results effectively. Apply improvement strategies and analyze a practical case study to see accessibility in action.

Making Content Perceivable

1. Which of the following helps make web content perceivable?

2. Why is color contrast important for accessibility?