Negative views of cats originated in the middle ages. In this period, people were more likely to believe in myths, fables, and legends about any subject. But much of the folklore surrounding black cats associated them with witches. Black cats were thought to be the "familiars" of witches, which means that they were the spirits of witches in animal form. Some people even thought these cats were reincarnations of witches from past lives.
I think black cats are magical, they often seem to be looking at you like they know what you are thinking.
I've got a few black cat penny charms in my etsy shop!.