
The purpose of Lent is the preparation of the believer — through prayer, penitence, almsgiving and self-denial — for the annual commemoration during Holy Week of the Death and Resurrection of Jesus, which recalls the events linked to the Passion of Christ and culminates in Easter, the celebration of the Resurrection of Jesus Christ.
In Western Christianity (with the exception of the Archdiocese of Milan which follows the Ambrosian Rite), Lent begins on Ash Wednesday and concludes on Holy Saturday. The six Sundays in Lent are not counted among the forty days because each Sunday represents a "mini-Easter", a celebration of Jesus' victory over sin and death.
[From Wikipedia]