The first book of the Old Testament, and subsequently the Bible, is Genesis and appropriately starts with the sentence, "This is the." This is part of the "Toledoth" formula. In Hebrew this phrase is "elleh tole dot" and it occurs eleven times in the Old Testament. This phrase also can be translated to mean: "these are the generations", "this is the family history", and "this is the account." The "Toledoth" formula sets up an interesting structure for the book of Genesis. It gives the book a prologue and then subdivides the book into ten subsequent sections; Adam, Noah, Noah's Sons, Shem, Terah, Ishmael, Isaac, Esau, and Jacob; ending at the deaths of the aforementioned men. .
The next approach to structure of Genesis is done in two parts the Medieval History, Creation through Tower of Babel, and the account of Abraham and his family for four generations. The chapters of Abraham and his generations are referred to as the Patriarchal Narratives. Both of these divisions begin with a creation by the word of God.
Still another division can be made between the Patriarchal Narratives and the story of Joseph. This distinction is made because it tells how one man, Joseph, brought the whole of Abraham's" descendents to the land of Egypt.
The genre of Genesis is pretty straightforward. It comes across a historical record of the distant past. However, many traditional non-Christian scholars believe it to be fictional. It is interesting that the narrative of Genesis carries the reader in an easy to read order from the creation to the sojourn to Egypt. It is interesting to note that there are no dramatic genre shifts from Genesis through the rest of the Pentateuch. The style of the book leaves to no doubt as to the intent of the author to provide a detailed, historical account of the beginning of the world to the displacement of God's chosen people to Egypt. Furthermore, it is even more affirmed by the Jewish and Christian, and by Christian I mean Non-Jewish believers, circles that the genre of Genesis is simply that of a Historical account of how things when down in the distant past.