Liberal Christians recognize that the writers of the Bible held a variety of beliefs concerning Heaven and Hell. The earliest books of the Bible described an underground cavern where all people, good and bad, spent eternity after death. The later books described Hell as either a place of annihilation or of eternal punishment. Generally speaking, this system of beliefs looks upon Hell as a concept, not as a place of punishment. The idea that a person would suffer eternal punishment for a single oversight, error or sin during life is seen as unjust. Punishment of an individual because she/he had never heard the Gospel is also viewed as irrational and unjust. They feel that a loving God would be incapable of creating such a place.
Conservative Protestant Beliefs
Generally speaking, conservative Protestants believe that everyone has the gift of eternal life. The body dies, but the soul lives forever. The big question is where each person will spend eternity. Heaven is a glorious location where there is an absence of pain, disease, sex, depression, etc. and where people live in new, spiritual bodies, in the presence of Jesus Christ. Hell is a location where its inmates will be punished without any hope of relief, for eternity. The level of punishment will be the same for everyone. The Bible talks about fire and (presumably flesh eating) worms.
The second major belief is that most humans will be sent to Hell after they die. Only those few who have been "saved" will go to heaven. Salvation requires repentance of sins and trusting Jesus as one's Lord and Savior. People who have been saved and make it to heaven will not all be treated equally. Believers who have done many good deeds will be rewarded more in heaven; believers who have led an evil life will be rewarded less.
Roman Catholic Beliefs
Hell is a location where its inmates will be punished without any hope of relief, for eternity. Among those punished will be Satan,