" ... According to the W3C, when you’re evaluating your web site for accessibility, you should ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen. How does one know if two colors will provide sufficient contrast? Well, the W3C, being the fastidious folks that they are, provide the following definition and formulas to make what seems subjective very quantifiable ... "