Traditionally, theologians concentrate on a list of specific categories within the field of systematic theology. Some of these categories include the following:
• Prolegomena, a technical term meaning "the beginning of the discussion," is often found in theology books to discuss introductory issues and definitions.
• Theology Proper (also called Paterology) is the study of what the Bible teaches about God the Father.
• Christology is the study of God the Son.
• Pneumatology is the study of God the Holy Spirit.
• Bibliology is the study of the Bible (also called special revelation).
• Soteriology is the study of salvation.
• Ecclesiology is the study of the church.
• Angelology is the study of angels (including fallen angels or demons and Satan, sometimes under the headings of Demonology and Satanology).
• Anthropology is the study of humanity (different from the field of anthropology since Christian anthropology focuses on the spiritual aspects of humanity).
• Harmartiology is the study of sin.
• Eschatology is the study of "last things," including biblical prophecy, the end times, and the afterlife.
In addition to systematic theology, there are many other ways in which theology can be studied. Some of the more common categories include historical theology, which is the study of a particular doctrine throughout history; dogmatic theology, which includes the study of a particular group's theology, such as Calvinistic theology or Arminian theology; and biblical theology, which develops the theology of particular biblical books or writers (such as Lukan theology or Pauline theology).
More recent areas of theology include contemporary theology, various ethnic- or gender-focused theologies (African theology, feminine theology), and philosophical theology (often included within the field of apologetics) which focuses on the rational evidence that supports Christian beliefs.
In summary, systematic theology is one of many ways to study theology, and the one way that specifically concentrates on an organized understanding of the Bible's overall teachings regarding important areas of faith.