The Bible was written by a variety of different people
OLD TESTAMENT
Genesis: Moses
Exodus: Moses
Leviticus: Moses
Numbers: Moses
Deuteronomy: Moses and probably Josua after Moses' death
Joshua: Joshua and probably high priest phinehas (eyewitness)after Joshuas death
Judges: possible Samuel
Ruth: Unknown, Samuel?
1 Samuel: Possible Samuel, includes writings from prophets Nathan and Gad
2 Samuel: Unknown, Nathan's son Zabud?, also includes includes writings from prophets Nathan and Gad
1 Kings: Unknown, possibly Jerimiah or group of prophets
2 Kings: Unknown:possibly Jerimiah or group of prophets
1 Chronicles: Ezra
2 Chronicles: Ezra
Ezra: Ezra?
Nehemiah: First person writing suggests Nehemiah, Ezra may have edited
Ester: Unknown, possible Mordecai or Ezra or Nehemiah
Job: Unknown, possible Job, Moses, Soloman, or Elihu
Psalms: David: 73, Asaph: 12, Sons of Korah: 9, Soloman: 2, Herman Ethan and Moses: 1, Anonomous: 51 (2 possibley by David)
Proverbs: Soloman
Ecclesiastes: Soloman
Song of Songs: Soloman
Isaiah: The Prophet Isaiah (son of Amoz)
Jeremiah: Jeremiah
Lamentations: Jeremiah
Ezekiel: Ezekiel (Son of Buzi, a Zadokite priest)
Daniel: Daniel
Hosea: Hosea (son of Beeri), (Hosea means salvation)
Joel: Joel (Son of Pethuel)
Amos: Amos
Obadiah: Obadiah
Jonah: Jonah (Son of Amittai)
Micah: Micah
Nahum: Nahum
Habakkuk: Habakkuk
Zephaniah: Zephaniah
Haggai: Haggai
Zechariah: Zechariah
THE NEW TESTAMENT
Matthew: Matthew
Mark:John Mark, not disciple, followed John on his first missionary journey
Luke:Luke
John:John the apostle
Acts:Luke
Romans: Paul
1 Corinthians: Paul
2 Corinthians:Paul
Galatians:Paul
Ephesians:Paul
Philippians:Paul
Colossians:Paul
1 Thessalonians:Paul
2 Thessalonians:Paul
1 Timothy:Paul
2 Timothy:Paul
Titus:Paul
Philemon:Paul
Hebrews:Paul, Luke, Barnabas, Apollos, Silas, Priscilla, and others
James:James (Jesus' Brother)
1 Peter:Peter
2 Peter:Peter
1 John:Apostle John
2 John:Apostle John
3 John:Apostle John
Jude: Jude (Brother of Jesus and James)
Revelation:Apostle John