The Particular Judgment: At the moment of death, every person receives his eternal reward or retribution in his soul. If he dies in the state of grace, in friendship with Christ, he receives entrance into heaven (either immediately or through purification). If he dies out of friendship with Christ, never accepting Christ's loving mercy, he remains separated from Jesus in eternal damnation.
Hell: We cannot be united with God unless we chose to love him. If we gravely sin against God, against our neighbor, or against ourselves and fail to repent and accept God's mercy, we will remain separated from him forever by our own free choice. This definitive self-exclusion from unity with God is called Hell.
Heaven: Those who die in friendship with God and are perfectly purified will see God as He is, face-to-face in Heaven. Heaven is the perfect communion of life and love with the Trinity and all the angels and saints. This perfect communion with God is the fulfillment of every human desire and the state of complete happiness.
Purgatory: There are some who die in friendship with God, and their souls are assured of Heaven, but they first must undergo a purification of venial sin and all attachment to sin before entering full communion with God in Heaven.
Prayers for the Dead: Catholics pray for the dead so that their loving intercession might contribute to the souls' purification and hasten their union with God in Heaven.
The Last Judgment: At the end of time, Christ will come again in glory, our bodies will be resurrected, and all humanity will face the Last Judgment, in which the truth of each man's relationship with God will be made known and the consequences of each person's actions will be revealed.