Moses is the primary author of Genesis through Deuteronomy (known as the Torah). He compiled the pre-flood manuscripts of the early chapters of Genesis, along with other manuscripts from which comprised Genesis. He wrote the other four books of the Torah during the 40 years Israel wandered in the wilderness. Joshua wrote most of the book bearing his name, while Samuel completed the final portion of that book, in addition to Judges and Ruth. Samuel edited his own additions, plus portions of the Torah.
Samuel also wrote much of the initial chapters of I Samuel (see I Sam. 10:25). The prophet Isaiah wrote the remainder of I Samuel as well as II Samuel and I and II Kings. Much of the work by Samuel and Isaiah was done by collecting and compiling older accounts recorded by prophets close to when the events took place. For example, Elijah had written much of what Isaiah compiled as part of the books of the Kings. I and II Chronicles, Ezra and Esther were recorded by Ezra, who was the primarily used by God to edit, compile and canonize the entire Old Testament.
The book of Job was most likely written by Job. King David wrote more than half of the Psalms. Others portions of that book were written by Moses, Hezekiah, Solomon and others. King Solomon also wrote Proverbs, Ecclesiastes and the Song of Solomon. Jeremiah authored the book of Lamentations.
Daniel, Ezra and Nehemiah wrote the books bearing their names. Isaiah, Jeremiah, Ezekiel, Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk, Zephaniah, Haggai, Zechariah and Malachi were all prophets God used to also record the books of the Bible that bear their names.
In the New Testament, the books of Matthew, Mark, Luke, John, James, I Peter, II Peter, I John, II John, III John and Jude were all written by the men after whom they are named. Luke also wrote the book of Acts. The apostle Paul wrote the book of Romans, I Corinthians, II Corinthians, Galatians, Ephesians, Philippians, Colossians, I Thessalonians, II Thessalonians, I Timothy, II Timothy, Titus, Philemon and Hebrews. The apostle John recorded the book of Revelation.
Much more details about the authors of the Bible are available in our booklet How We Got the Bible – Which Translations Are Best?