Making sense of accessibility in IT design - usable accessibility vs. accessible usability

The Internet with its nearly unlimited offer for information, services and functionalities for communication has become an essential part of business and private life within the last years. Recent information and communication technologies (ICT) together with the Internet offer also new impressing possibilities for people with disabilities. However people with disabilities often hit barriers when using ICT and the Internet. Usually, this is not because of the restricted users information perception (visually, auditory, haptic) - people with special needs use assistive technologies that compensate particular disabilities. Mostly, they cannot make use of ICT and the Internet because designers and developers do not follow rules and guidelines for accessibility and usability. Comprehensibility, clarity, readability, high-quality, up-to-dateness and intuitive operation and use, are important criterions that are essential for customer satisfaction, loyalty, quality and success. Therefore accessibility and usability has important advantages for all users, not only for people with disabilities.