Satan
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Satan, in the Christian religion, is a former angel that left God and took many other angels with him. He did this because he wanted to be better than God. According to the Bible, he will be punished in eternal Hell fire, along with all those who join to him. He is sometimes called the devil or Beelzebub. Christians believe he tempts people to do bad things. Some also call him Lucifer, but this name is from Roman belief, not the Bible.
Originally the name means the accuser, the enemy. In abrahamitic faiths (Judaism, Christianity, Islam) his role is to question and tempt the faith of humans. Many times, he is also seen as a demon.
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