The Bible can be broken up into categories:
1.. The Laws and Religious instruction
a. Jewish Law
b. The Epistles (letters) to the New Testament Church
2. Various insights into human interaction and instructions, Wisdom
Proverbs, Ecclesiastes.
3. Poetry
Psalms, Song of Solomon
4. History
a. Books like Judges, 1 & 2 Samuel etc.
b. New Testament Gospels, Acts
4. Revelations from God
a. The Old Testament Prophetic books, Isaiah, Jeremiah, etc.
b. The New Testament's book of Revelation (and prophecy scattered throughout including the Gospels)
All of the (Protestant) 66 books of the Bible were written by Jews and written over (common estimate) 1500 year period. A lot in Israel had changed during that time. Some books were simply letters, like the epistles. Some were compiled historical records, like Chronicles. Some were oral traditions, stories of the creation, the Patriarchs etc., which were eventually written down.
The Jews were very meticulous in their record keeping, as well as maintaining the historical tradition and beliefs from the past. However, human nature, vulnerabilities, subjectivity, bias's, prejudices, with personal inclinations of nationalism, created a very human book. Thought it has wonderful spiritual insights scattered throughout, it is still not perfect.
For the Old Testament Bible to be perfect, its writers would have to have something better than what we have today! We now have the story and teaching of Jesus, The New Covenant, The New Testament, The gift of the Holy Spirit. But, we are told by our present day Bible teachers, 'we cannot receive the same kind of inspiration they had.' This flies in the face of reason.