Principle 4 - Robust

Guideline 4.1 - Compatible

Maximize compatibility with current and future user agents, including assistive technologies.

4.1.1 - Parsing - Level A
All pages should validate when possible.

4.1.2 - Name, Role, Value - Level A
Use aria-label, aria-labelledby, and other elements to identify form fields when a visible label is not an option.

4.1.3 - Status Messages - Level AA
Use role to identify status messages, alert messages, etc, so that assistive technologies can present these messages without receiving focus.