This site is about color blindness or, more correctly, color deficiency.
Briefly, it describes the condition, causes, and effects. The primary purpose, however, is to furnish a set of color charts to aid the color blind in working with computer colors, most especially on the internet and in web sites. There is also some really nice software (shareware/freeware) here for checking colors onscreen on your computer – great for anyone, but especially for the colorblind!
About the Color Charts
There is one column named “Co#” in each color chart. If you need to find colors that will work satisfactorily together in a single web page, you can use any colors with the same Co# (Coordinating Number) and feel safe with them. Not every chart nor every color has a Co#. Depending on the colors, some colors may appear in more than one color chart grouping.