Black cats bring luck
For a long time people in Great Britain have been thinking that if the black cat crosses your way or enters your home it means luck. This custom has three sources.
The first one is connected with the Ancient Egypt where people thought that the cat brings happiness in the house where it lives and to people who take care about it. Of course, the real use was the reducing of the number of mice in the house. But because of many different myths and legends positive role of cats grew and it become something absolute. The inscriptions on the ancient tombs says us that "the cat gives us life, happiness and health, it does it every day and provides the quiet old age". Cat must be in every house. Through the thinnest sources this ancient tradition come from one century to another even when the Christian church prosecuted cats as "the devil's servants".
The second source descends from medieval period when people hated "cat-devils" and were afraid of them. Just at that time the popular belief was born: if the cat had crossed your way and then you didn't suffer, then it meant that you were lucky. That's why the association between cat and fortune arose. If the cat comes into your house and you takes care of it you get the good attitude of devil and protect yourself from his anger. That's why when the cat comes into your house and gets the good care you'll get in exchange for that fortune and good relation of devil. He may trouble anyone but you.
The third source is more earthy. The old English proverb says: "If there is a black cat in your house the lovers will always be there". Here the cat plays the role of a symbol of sexual attraction. During the current period she attracts the crowd of cats, that's why the house where she lives is considered as the place where any female will have the popularity among the crowd of men.
The black is especially the lucky color in all these cases because it is associated with cult practice, but on the other side of Atlantic, in America, it is all the other way round: they think that the white cat brings fortune and the black one brings troubles. It is connected with the fact that in the times of pioneers, the first settlers, the black cat was associated with devil so much that nobody even tried to make the situation better. But the white cat, on the contrary, was considered as the power of light opposite against darkness and that's why it was considered as the sign of fortune.