Amazon.com description: Product Description: Christianity is the world's largest religion. Almost 1,500 million people belong to its many thousands of different groups. This book presents the often bewildering variety with care and understanding. It looks at the first Christians, and traces the customs and beliefs of today's four great families: Orthodox, Roman Catholic, Protestant and Pentecostal. It clarifies their many shared and unique practices, and explains why the centre of faith for all Christians is Jesus, the Christ.