The literary genres of the book of Revelation are an Apocalypse, a Prophecy, and an Epistle (or Letter). The Disciple/Apostle John, who followed Jesus Christ and witnessed His crucifixion, authored it. John wrote Revelation while a prisoner on the Island of Patmos, approximately 85-95 A. D. Its purpose is to give encouragement and hope for all Christians to continue watching for the return and triumph of the Lord Jesus Christ.