Assistive Technologies
Assistive technologies are hardware and software aids that enable people with disabilities to use digital content, among them screen readers, screen magnifiers, voice control software, switch input devices and braille displays.
In practice
Rather than building for one particular tool, it pays to attend to the underlying principles all these aids rely on: semantic HTML, full keyboard operability and sufficient contrast. Designing that way improves compatibility with the whole range of assistive technologies, instead of catering to a single screen reader. Regular testing with different tools and, where possible, with people who actually use assistive technologies is a useful complement to automated checks.