There are many branches in philosophy, and it's easy to mix them up. Depends on what you're into.

• Ethics: notions of right and wrong and moral values.
• Epistemology: questions of knowledge. How do we know what we know.
• Metaphysics: ideas of space, time, existence.
• Aesthetics: appreciation of art, beauty, music, literature, etc.
• Logic: for the math-oriented. How do we reason and arrive at conclusions? If X, then Y.
• Language: how we communicate. Meaning of words, symbols, and metaphors.
• Phrenology: method of relieving cranial pressures.
• Science: how to reason about the physical world.
• Religion: Understanding the divine and how we fit in.