Though the Bible was written chronologically depending on time some mistakes were made in reference to that time but the mistakes are negligible the message are compatible from one to another from the Book of Genesis to the last book of Revelation. There 8 accepted books of the Bible namely; Historical, Poetical, Major Prophets, Minor Prophets, The Gospels New Testament Historical, Epistles and the Prophetic Book Revelation.

http://www.christianity.com/Christian%20Foundations/The%20Bible/11528149/

According to Christian foundation, Historical books purpose is to trace the origin and history of man, the Poetic Books brings out the civilization of man and the experiences of human heart, while the last division of the Old Testament which is the Prophetic Books exposes the theme...

Nevertheless, the book of Revelation is described as the letter of Jesus.
References

http://truekingdomofgod.org/bible/bibleorganization.html

http://www.about-jesus.org/Bible.htm

http://www.christianity.com/Christian%20Foundations/The%20Bible/11528149/

http://www.holyBible.com/resources/KJV_DFND/summary.htm