Contrition: A sincere sorrow for having offended God, and the most important act of the penitent. There can be no forgiveness of sin if we do not have sorrow and a firm resolve not to repeat our sin.
Confession: Confronting our sins in a profound way to God by speaking about them, aloud to the priest.
Penance: An important part of our healing is the 'penance' the priest imposes in reparation for our sins.
Absolution: The priest speaks the words by which 'God, the father of mercies' reconciles a sinner to himself through the merits of the cross.