Christians around the world are marking the beginning of Lent.
Many will go to church to have a priest smear ashes on their forehead.
The ashes symbolize mourning and penance.
They also remind the faithful of their mortality.
Many Christians give up something tangible for Lent such as liquor or a favorite food.
They may also reflect on their lives and decide whether to make changes.
They try to purify themselves for Good Friday, which marks Christ's death on the cross, and for Easter Sunday, which celebrates his resurrection.