It’s a tool that brings attention and understanding to how color contrast can affect different people with visual impairments.
The Web Content Accessibility Guidelines (WCAG) covers a wide range of recommendations for making Web content more accessible. Just a tiny part of making the web more accessible is accommodating for those with a form of blindness or low vision.
The standard grading system is a great start, but @CoreyGinnivan thought he’d try to humanize the people who are affected by the different grades.
whocanuse.com