It begins on Ash Wednesday, when a priest places ashes on the head or forehead of Catholics and invites them repent.
The ashes come from the olive branches that were blessed on Palm Sunday from the previous year.
Every Friday of Lent, the Catholic Church asks everyone to not eat meat as a sign of penance. They also hold a fast on Ash Wednesday and Good Friday.
The Church also urges Christians to practice other forms of piety such as giving alms, making a pilgrimage or any other willful deprivation to prepare for Easter.