Black is darkest color which is the result of the absence or complete absorption of visible light. Black colour is commonly used used for printing books, newspapers and documents. Normally black colour phone look very beautiful like mine Iphone which is black in colour and looks beautiful.
Black colour cat is considered as witches
Black cats are associated with Satan, witches and witchcraft and some people believe that black cats were cohorts to witches or even witches. With this mass killing of black cats where done and sometimes even their owners where killed. Some people also think that if black cats croses your way while driving then it is considered as bad luck. I think it is just psychology that you think black cat are bad luck but your luck is in god hands.