Merging Web Accessibility and Usability by Patterns

Nowadays, usability and accessibility are two important quality aspects of user interfaces (UIs). But in research and development, both are sometimes accounted as unity and sometimes as contradiction. Understanding Web accessibility as an essential part of usability, here an approach is given to clarify the relationship of both. Therefore, – a pattern approach was chosen to meet the practical requirements of UI designers which are often not familiar with accessibility needs, – a collection of patterns for human-computer interaction (HCI) has been extended with accessibility requirements and – finally a pattern example illustrates the cooperation of usability and accessibility in detail.