Iblis is the name used in Koran for the primary devil, the equivalent of Christianity's Satan. He is popularly known as Shaitan, the fallen angel. It is said that this evil character was a jinn made of smokeless fire.
Etymology: Some believe that Iblis is derived from the Greek word diablos (evil), though there is not much evidence of this. Some say that the word Iblis means despair. It is also said that Iblis was actually an angel named Azazel.
Iblis was believed to be very close to Allah (God) originally, but Iblis disobeyed Allah and was immediately expelled from His grace. He was permitted to live only in ruins and eat unblessed food.
It is believed that Iblis lured Adam and Eve to eat the forbidden fruit and was then condemned by Allah to Hell. Later when he requested that he should be allowed to take some humans along with him, Allah agreed and let him roam the earth and lure people who had no self control or faith in God.
The Koran says Iblis is not Allah's rival as such, he is just another creation of the Almighty.
According to belief, Iblis whispers the suggestion of sin into people's ears and lures them. The day will come when Iblis too will go to Hell along with all the people whom he lured, but until then he roams on earth.
It is said that once Iblis gathered an army of jinns and began ruining the earth until Allah sent angels to capture him and stop the catastrophe. Iblis was brought to Heaven and taught honesty and love but later he again fled to continue his evil ways.