Since 1999, under the Disability Discrimination Act, it has been a legal requirement for UK websites to be accessible to all users. It is recommended that websites should now be built following the W3C-WAI Web Content Accessibility Guidelines and government legislation on accessibility (Disability Discrimination Act).
Using XHTML and CSS ensures that sites are accessible to all users whether using regular browsers, braille readers, screen readers and so on. XHTML & CSS is the most efficient and up-to-date technology for building websites; it separates content and mark-up (HTML) from design, resulting in smaller file sizes and therefore faster download times.