There are 12 Minor Prophets in the Old Testament: Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk, Zephaniah, Haggai, Zechariah and Malachi. The five Major Prophets are Isaiah, Jeremiah, Lamentations, Ezekiel and Daniel. The "major" and "minor" designations have nothing to do with the importance of the prophecy. All the prophets, major and minor, are important. These designations have to do with the length of the prophecy or book. The Major Prophets are longer and the Minor Prophets are shorter in length.
Of these 12 Minor Prophets, the first nine are pre-exilic (preceding the Assyrian exile in 722 B.C. and/or Babylonian exile in 586 B.C.) and three are post-exilic (during the time of the Jewish return from Babylon to Jerusalem).
Rarely will you ever hear a sermon series on the Minor Prophets or even a Sunday School course of lessons. This is a shame as the Minor Prophets have much to tell us about humankind and especially about God Almighty. Here, gathered in 12 lessons, one on each Minor Prophet, you will learn the thrust of each book. May it motivate you to read and study the Minor Prophets in greater detail. You will greatly benefit, if you will do so.