Quick Answer: Accessibility is the design of products, devices, services, vehicles, or environments to be usable by disabled people. The concept of accessible design and practice of accessible developments ensures both "direct access" and "indirect access" meaning compatibility with a person's assistive technology. Accessibility can be viewed as the "ability to access" and benefit from some system or entity. The concept focuses on enabling access for people with disabilities, or enabling access through the use of assistive technology; however, research and development in accessibility brings benefits to everyone. Therefore, an accessible society should eliminate digital divide or knowledge divide. Accessibility is not to be confused with usability, which is the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use.