Who was Morgan le Fay?

Morgan le Fay, alternatively known as Morgane, Morgaine, Morgana and other variants, is a powerful sorceress in the Legend of King Arthur and the knights of the round table. Although there are records to prove King Arthur's exsistance, many scholars believe that he was less of a deal than the tales give appearance to.
i have no idea who he or she was.....if you know please tell me but i have to tell u

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she was king arthur's sister

Okay, yes Morgan was Arthur's half sister, She was very deceiving, at one time she stole excalibur and gave it to her love, so when arthur fought her love, he would be powerless.