Who is Satan?
The Bible says that Satan was created by God as a cherub, the most powerful of God's angelic beings. Some time after his creation and before the creation of mankind, Satan rebelled against God and took one third of the angels (now referred to as demons) with him into rebellion.
What does Satan look like?
No, Satan does not look like the cartoon character in the red suit with a tail and horns and a pitchfork. Angels, including Satan, don't have male or female characteristics in their heavenly state (which Jesus told us through His teaching). However, when they come to earth, they can take on human form. In the Bible, all angels who take on human form appear as males. All biblical references address Satan by the personal pronoun "he."
However, in their heavenly state according to the Bible, a cherub is a large creature—up to 18 feet in height with 8 foot long wings. In the prophet Ezekiel's vision, the cherubim (plural of "cherub") had four wings. Under their wings were human-like hands that could could be used to carry things. All the surfaces of the cherubim, including the wings, were covered with eyes. Each cherub had four faces, one "of a cherub, the second the face of a man, the third the face of a lion, and the fourth the face of an eagle." The New Testament book of Revelation describes similar creatures, only with six wings each, with faces of a lion, an ox, a man, and an eagle. So, these creatures look nothing like the cute little cherubim you can buy for your garden or bookshelf. Satan himself is described as being "perfect in beauty," being adorned with all kinds of precious stones.
The fall of Satan
Satan was created as a perfect being. He is described as originally being wise and completely righteous. However, pride caused Satan to fall, ("your heart was lifted up because of your beauty"), since he wanted to receive the worship due to God alone. At that point there was rebellion in heaven, when Satan convinced one third of the angels to rebel against God. Michael, an archangel of God, fought with God's angels against Satan and his angels, with Satan losing the battle and being cast from heaven down to earth.
However, Satan wasn't finished in his rebellion against God. Satan took on the form of a snake in the garden of Eden to tempt Eve. He managed to convince Eve that God's instructions against eating from the tree of the knowledge of good and evil were done as a way of keeping something good from her. She believed Satan's lie that she would "become like God." We don't know where Adam was at the time of Satan's temptation, but he followed his wife's lead and also disobeyed God's instructions.
Satan's ultimate fate
The Bible says that Satan will continue in his rebellion against God until the very end. Near the end, a "beast" (world ruler) will arise from the "sea" (the gentile nations), having been given power by Satan to perform signs and wonders for the world. In addition, a false prophet, a religious leader empowered by Satan will deceive people into worshipping him. The beast and the false prophet will convince the leaders of the earth to follow them into war against God and His people. However, the armies of the leaders of the world will be destroyed at the battle of Armageddon and the beast and false prophet will be thrown into the Lake of Fire. At this point, Satan will be locked up for 1,000 years, while Jesus Christ rules the earth with His saints. At the end of that period, Satan is released for a short period of time, deceives the leaders of the world again, and convinces them to attack Jesus and His rule on the earth. The battle is short as fire from heaven consumes the rebels. Satan is then thrown into the Lake of Fire (hell) to "be tormented day and night for ever and ever." Following Satan's demise, the saints of Jesus Christ will judge the angels who joined him in rebellion.
source: http://www.godandscience.org/doctrine/who_is_satan.html
