Theology is the study of God and the nature of the Divine. This is sometimes considered a whole separate branch of philosophy, the Philosophy of Religion (see that section for more detail). It asks questions like:
Does the Divine intervene directly in the world (Theism), or is its sole function to be the first cause of the universe (Deism)?
Is there one God (Monotheism), many gods (Polytheism) or no gods (Atheism or Humanism), or is it impossible to know (Agnosticism)?
Are God and the universe identical (Pantheism, Monism) or are they different (Panentheism, Dualism)?
Does religious belief depend on faith and revelation (Fideism), or on reason (Deism)?
Within Western Philosophy, Philosophy of Religion, and theology in general, reached its peak with Medieval Christian schools of thought like Scholasticism.