Web Design for the Color Blind

Even though the colour blind people are not actually blind we can classify them into a group of vision impaired people. There are different types of colour blindness but in general those people are facing the inability or decreased ability to see colour or perceive colour differences under normal lighting conditions. This might lead to limited or incorrect perception of websites. The requirements for colour-blind-friendly websites are part of the “Web Content Accessibility Guidelines (WCAG) 2.0” and point out the importance of colour blindness in the context of web design. 

8% of the male population and 0,5% of the female population are colour-blind. Unfortunately most of the websites do not take this into consideration and do not think about colour blindness when designing their websites. It is really important that at least the most crucial information on the website is designed in colour-blind-friendly way. This can easily be tested using colour contrast checkers, many of which are available for free. It is evident from the fact that there are simulations of two colour blindness types available in Photoshop that colour blindness is also becoming important part of a designer's work.

There are many different forms or types of colour blindness, some of them are quite common and some are rare, but we still have to consider all of them if we want to create accessible and well preserved design. An important facts is, that more than 99% of all colour-blind people can see colour. The assumption of seeing only black and white, which comes out of its name is therefore completely wrong. Colour-blind people are not actually colour blind but just colour deficient. The deficiency is different in each of the types which make colour-blind people part of different user (sub-) groups. Within all the different forms there are however also varieties in the severity of colour blindness. Usually the severity is divided into four categories: absolute, strong, moderate and slightly severity. Slight colour blindness may barely vary from the normal vision. 

One of the color blindness simulator pages :http://www.color-blindness.com/coblis-color-blindness-simulator/

Great sources to learn about color blindness are:

http://wearecolorblind.com/

http://www.color-blindness.com/what-is-color-blindness/

Very interesting for designers (print or web), is the following link: https://designshack.net/articles/accessibility/tips-for-designing-for-colorblind-users/