Summary  
This chapter explains how to implement accessibility features in code by using semantic markup and ARIA attributes to add alt text for images, ensure sufficient color contrast, enable keyboard navigation, label form controls, and announce dynamic content to assistive technologies.  

General domain of usage  
Web development

When interacting with websites, users can face a variety of obstacles that make it difficult or even impossible to access content and complete tasks. These obstacles are known as **accessibility barriers**. Understanding these common barriers is crucial to creating inclusive digital experiences. Some of the most frequent accessibility barriers include:

- Missing alt text for images; 
- Poor color contrast between text and background; 
- Lack of keyboard support for navigation and interaction; 
- Confusing or inconsistent navigation structures; 
- Inadequate labeling of form fields and controls; 
- Reliance on color alone to convey information; 
- Non-descriptive link text, such as "click here"; 
- Dynamic content updates that are not announced to assistive technologies.

Missing **alt text** means that users who rely on screen readers cannot understand the content or function of images, making the site less informative. **Poor color contrast** can make text unreadable for users with low vision or color blindness. If a website lacks **keyboard support**, users who cannot use a mouse are unable to navigate or interact with the site. **Confusing navigation** can leave users lost, unable to find the information they need. Each of these barriers excludes people with disabilities from fully participating online, highlighting the importance of accessible design.

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**Assistive technology** refers to hardware or software tools that help people with disabilities interact with digital content. Examples include screen readers, screen magnifiers, speech recognition software, and alternative input devices. These technologies help users overcome accessibility barriers by providing alternative ways to access or interact with web content.

Definition

Which of the following is a common accessibility barrier?

How do assistive technologies help users overcome accessibility barriers?

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.

Common Accessibility Barriers

1. Which of the following is a common accessibility barrier?

2. How do assistive technologies help users overcome accessibility barriers?