HTML and its related technologies, like XHTML and CSS, offer the most flexibility in terms of support on different devices and platforms and support for people with disabilities.
As with any technology, there are both accessible ways and no-accessible ways to build Web pages. Accessibility does not happen by accident with Web pages. Web pages need to be designed from the beginning with accessibility in mind.
Web pages delivered as HTML have the most flexibility in terms of creating an accessible experience.
Follow established Web accessibility guidelines and practices. Refer to the Accessibility Handbook.