What is a Doppelganger?

Okay, so I need the definition of a doppelganger. who/what is it?



Also, i have to know how Bertha Mason is Jane Eyre's doppelganger. (from the book Jane Eyre) you don't have to answer that one, but if you can, it would be helpful! :)What is a Doppelganger?
What is a dictionary?

http://www.merriam-webster.com/dictionar鈥?/a>
Doppelg盲nger is a ghostly double of a living person, especially one that haunts its fleshly counterpart.



(German, a double : doppel, double (from French double) + G盲nger, goer (from Gang, a going, from Middle High German ganc, from Old High German))



Jane Eyre is not one of my reading books.What is a Doppelganger?
Doppleganger





A double or identical replica of a person. The concept revolves around the belief that everyone has a doppleganger, an identical copy of themselves somewhere in the world. If the person is good then the doppleganger will be evil and vice versa. It is even said that if the two should meet then they will both perish.



There have been a few reports over the years of ordinary people who have come face to face with someone who is identical to themselves, while random chance would seem to exclude the likelihood of randomly encountering an individual who is physically identical to yourself it isn't impossible.



Most people agree that the concept of a doppleganger is little more than a myth.What is a Doppelganger?
A doppelganger is someone who looks like another person. The doppelganger, story wise, traditionally takes the place of the original person and a highly nefarious plot ensues henceforth.
doppelganger means a guy who looks exactly like you but different personalty
an exact double but not a twin.