Types of assistive technology
Assistive technologies help people with a variety of abilities
- Screen readers interpret the underlying document object model (DOM) of your software or website to convert content and navigation into spoken words or other forms, like Braille.
- Tools and settings provided by the operating system include captions to convert audio to text, and high contrast themes and screen magnification to make displays easier to see.
- Virtual keyboards let users type text using a pointer.
- Alternative input devices include motion-activated technologies, such as motion or eye tracking devices, single-switch entry devices, head pointers, and so on.
- Voice-recognition software uses words spoken by the user to interact with the software or website.
Custom controls
WAI-ARIA, the Accessible Rich Internet Applications suite, defines a way to make Web content and Web applications more accessible to people with disabilities.
If you're developing specialized controls or dynamic content, you need to provide instructions about the type of control and its role to assistive technologies. While standard HTML controls and tags are recognized and announced by assistive tools, such as screen readers, customizations developed with other technologies (such as JavaScript, including Ajax) do not have this advantage. To ensure that your customized controls are recognizable to assistive technologies, follow ARIA guidelines to ensure that names, roles, and states of your controls are coded properly.
Best practices
- Test that components behave as expected when using a screen reader. For example, check that that a skip-to-content link is present.
- Test components using only a keyboard to make sure that the tab order is logical and that there are no traps.
- Use buttons where possible as they are activated by keyboard enter or spacebar and keep focus.
- If using custom controls (such as accordions), make sure to embed ARIA roles and attributes.
- Don’t assume that screen readers will identify all visible content or that only visible content will be announced.
- Don't use nonstandard interactions.