The Sacrament of Reconciliation (also called Confession or Penance) has three elements: conversion, confessions, and celebration. In it we find God's unconditional forgiveness; as a result we are called to forgive others.
"In the Sacrament of penance, by naming and confessing our sins before the priest who represents Christ, we face our failings more honestly and accept responsibility for our sins. It is also in Confession that a priest and penitent can work together to find the direction needed for the penitent to grow spiritually and to avoid sin in the future." ~ Catechism of the Catholic Church, # 1455, 1456.