THE CATECHISM was born in the first age of movable type. Among the books which poured from the presses and accounted for a large part of the first generation of the communications explosion' were 100,000 catechisms by Martin Luther, who first used the word to title a book in 1529.2 In explaining the truths which a Christian must believe, these earliest catechisms followed a predictable format and table of contents. Cardinal Bellarmine sums up four "principal and most necessary parts": "to wit the crede, the Pater Noster, the ten commandments and the holy sacraments."3 The Apostles' Creed was explained phrase for phrase. The importance of prayer and the Our Father as the central Christian prayer were explained. The ten commandments were enumerated and explained one by one. The same was done with the seven sacraments. This content, though not always in the same order, can be found in every catechism.