what is a doppelganger

A doppelganger is a biologically unrelated look-alike, or a double, of a living person. The word comes from German and means "double goer". In literature, a doppelganger is the double of another character, often similar in looks but differing in values and choices, leading them down a different path. In fiction and mythology, a doppelganger is often portrayed as a ghostly or paranormal phenomenon and usually seen as a harbinger of bad luck, or even an evil twin. Sightings and reports of doppelgangers have been around for centuries, and a great deal of superstition has developed around them. In many cultures, a doppelganger is seen as a bad omen or a sign of impending death, but some cultures view the appearance of a doppelganger as a positive symbol of protection or good fortune.