The purpose of Hell is two fold; to scare the mortals whose destiny in Heaven or Hell has not yet been determined, and to punish the souls of those who made the wrong choice. It is defined loosely as a place where people are consciously tormented for all eternity as retribution for their sins in this world.
Christians have no recourse if they want to deny the existence of Hell. Jesus mentions Hell several times in the New Testament and is very clear not only that one exists, but also that sinners are destined to go there (Matthew 5:30, Matthew 10:28, Matthew 23:15, Matthew 23:33, Luke 10:15, Luke 16:22-24 etc). To deny Hell is to deny that Christ was infallible and therefore cease to be a Christian.
Since faith is what pleases God, and it is impossible to please (or believe in, for that matter) God without faith, it follows that we must also have faith in the existence of Hell before we can fear going there. If God were to prove to us that Hell existed, we would all immediately fall into line and do whatever he said, because only a madman would want to go to Hell when he could easily go to Heaven.
But God isn't so kind to us. He merely threatens us with hell through intermediaries rather than showing it to us. There are those among us who do not think the ramblings of a person who believes and says he is the Son of God should be taken seriously; these days, such a person would be locked up.
These people, unlike the faithful, do not make a choice in what to believe - the faculties of intellect and reason with which God has endowed them make it impossible for them to believe in Hell. In other words they have not been given the "gift" of "faith." This is quite hard for the faithful to understand; they ask, "Why do you lack faith? Why don't you believe what we all believe?" The faithless are at a loss to explain, because the faithful have a choice that they do not.
Assuming the faithful are right, and Hell does exist, the faithless can only be classified as ignorant since they have not been supplied with adequate information or the "gift". This is not their fault. God made them the way they are, and if God wants them to go to Heaven, he should give them more of a chance than he has. The intellect of God more than dwarfs the intellect of man, yet God wants us to operate at his level.
We have yet a third person who is guilty of having no faith; the uninformed. The one who has not even been informed of the existence of Hell or God. Recall the story of the Christian missionary telling an Inuit tribe about Jesus and Heaven and Hell. One of the tribesman asked him, "If you had not told me about Hell, would I have gone there when I died?"
"Oh no, certainly not," said the missionary.
"Then why did you tell me?" said the man.
That story may be amusing, but unfortunately not all Christians are in agreement with that missionary, and the Bible hasn't much to say about it, except that sinners go to Hell without providing an exemption for people who never knew that sin was a bad idea.
So what are we left with? The only people who go to Hell are the ignorant, the uninformed, and the insane. They are punished for all eternity for sins they had no way of knowing they were comitting and no way of escaping. If God were benevolent, he would not send the innocent to Hell. God does not love you. The classical villains of history - Hitler, Stalin, Pol Pot - all pale in comparison to the Christian God.