They are classed as major - longer lives- and minor - shorter lives and service as prophetic workers for God.
Major included Jeremiah, Daniel and Isaiah and minor, Amos, Malachi and Obadiah.
Unlike some of the other writers of the 66 Bible books, prophets were not just writers but spoke out God's Wisdom AMONG THE PEOPLE. Obviously, God told them to say things He wanted changing and there was resistance and also awe. Some listened and followed and others rejected the revelations from God. Everything that has happened in the world and is happening now, was prophesised in the Bible thousands of years ago. We are in God's final stages of His plans for the world He planned.