The idea about Friday the Thirteenth is totally ridiculous . I don't believe it at all .   Maybe you can't be so sure .   Why not ? The whole idea is superstitious .   But some people use this occasion to create trouble . Have you heard of the Black Friday Virus on the computer ? It is designed to break out on every Friday the Thirteenth .   I know that . But that has nothing to do with being unlucky . Those who created the virus are deliberately making fun of people . 