The Book of Jubilees (also called Lesser Genesis) is an ancient writing that claims to be revelation given to Moses regarding the division of the days, weeks, months, and Jubilees of the Law. These Jubilees are considered 49-year periods of time in which all of world history is divided. The material included in the Book of Jubilees often overlaps with the Book of Genesis. Additional details are provided, however, such as names for Adam and Eve's daughters, the chronology of time prior to Moses receiving the Law, four classes of angels, an interesting interpretation regarding the Nephilim of Genesis 6, and that Hebrew was the original language of the world.