The most important Christian belief is that Jesus died to save mankind and then came back from the dead. This return to life is called the Resurrection.
Christians see Jesus’ resurrection as proof that there is life after death. Christians believe that they have only one life on earth. After that life the body dies but the soul (the spiritual part of a person) lives forever. Christians believe that, after death, God will judge each soul.
Christians believe that God will make a judgment based on whether that person lived his life in the loving way that Jesus taught and whether that person accepted Jesus as the Son of God. Even if a person has not done so Christians believe that a soul can still go to heaven if that person truly repents his sins (is sorry for all he had done wrong).
Jesus taught that on the day of judgement those people who had lived as Jesus had taught and behaved in a loving way would go to heaven (God’s kingdom), to start of a new life with God. Those who had not would go to hell (a place of punishment for the wicked.)
One issue, on which all Christians have yet to agree, is whether a soul goes to hell forever or whether it will one day be saved because of the Atonement. The latter belief is called Universalism.
Whatever they believe however modern Christians place much less emphasis on hell and damnation than did Christians in earlier times.