This book is written for all who are learning to pray. It is written firstly for lay people, to introduce them to one of the Chruch's greatest treasures of prayer, the Divine Office. The word 'Office' comes from the latin officium, meaning 'service', 'something done for someone'. The Divine Office is the service given to God in prayer. The Office is also called the Liturgy of the Hours, referring to the seven 'hours', or times of prayer for each day. It is part of the public liturgy of the Church.