Make it easier for people to complete input fields requesting personal information. People with mobility issues have difficulty entering data into the fields. People with cognitive disabilities may have difficulty remembering details. It may be hard for them to enter personal information due to memory loss, dyslexia, or other impairments.

Developers should use autocomplete on fields that collect personal data to explicitly identify the data type. Use the list of  Input Purposes for User Interface Components to select the correct value. Turn off autocomplete for sensitive information.

^{(Source: Knowbility article on input purpose)}

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People with visual, cognitive and physical impairments are particularly prone to making errors when entering data through forms. When errors resulting from form input happen, it’s important to make sure that error messages are shown accessibly.

• Provide error messages that give assistance: Describe the related problem in straightforward terms and, where possible, give advice on how to resolve them.
• Make it easy to locate the problem: Programmatically associate each error message with its...

Users of assistive technologies must understand what a custom control is and what it does. Custom controls that lack accessibility information become difficult or impossible to understand or operate. Using WAI-ARIA provides a way to fill in missing accessibility information so that assistive technologies can recognize custom controls as controls and not as div or span elements without semantic meaning or value.

• Provide an accessible name for each custom component. An accessible name is effectively the label for a control, explaining what it does....

Forms allow users to enter data by typing or selecting from a set of options. When forms are not designed with accessibility in mind, people with disabilities are likely to have difficulty or even find it impossible to enter data without errors. So forms need to be designed so that the purpose of each control is clear.

• Provide an accessible label for every control. Preferably, give each control a visible text label that explains its purpose. This is best done with an HTML label element that’s programmatically associated with the control....