This system was developed with the goal to provide equal access to all users, including people with handicaps and/or special needs. Neutrality to user's software, hardware and settings was also carefully pursued. Thus the result should be well usable with all common types of devices, screen sizes, operating systems, browsers, font types and sizes, assistive technologies etc.
The development considered formal accessibility standards, such as Web Content Accessibility Guidelines 2.0 or Section 508 as well as real end user experience. Accessibility and usability was tested with different combinations of assistive technologies, especially screeen readers.
You will find information about navigation and accessibility related features in the chapter Navigation of the User's Manual.