bad luck

Why is Friday 13th considered 'unlucky day'?
friday 13th or black friday is an unlucky day in many people's notions. so what is the origin of this friday and the 13th and why is it considered a bad day?
Cold with the mysterious stories about the 'ghost of the living'
doppelganger is meant to be a twin, a term for the ghosts of a person who is still alive. therefore, they are considered bad omen, warning signs of death are near. many people believe that it is just an illusion but historically has recorded some scary stories about doppelganger.