Accessibility
Contrast
In short and in plain language
Contrast is the difference in brightness.
It means the difference between the text and the background. There are minimum values for contrast.
Good contrast helps everyone. It helps most of all people with poor sight. It also helps in bright light.
Definition
Contrast is the difference in brightness between text and background. The WCAG set minimum values for it. Good contrast helps everyone, especially people with low vision or in bright light.