Our Father
The Lord's Prayer
Given by Jesus to his disciples when He was teaching them how to pray. (Matthew 6, Luke 11)
Our Father, who art in heaven, hallowed be thy name; thy kingdom come, thy will be done on earth as it is in heaven. Give us this day our daily bread, and forgive us our trespasses, as we forgive those who trespass against us; and lead us not into temptation, but deliver us from evil. Amen.
Origin
Given to us by Jesus himself
When to pray it
We pray it during Holy Mass, we pray it during the Rosary, but it's the perfect prayer for any time. It's how Jesus prayed, and imitating Him, we pray it too.