Epistemology

Epistemology, from the Greek words episteme (knowledge) and logos (word/speech) is the branch of philosophy that deals with the nature, origin, and scope of knowledge.

Metaphysics

Metaphysics (derived from the Greek words "ta meta ta physika biblia") - meaning 'the book that follows the physics book'. It was the way students referred to a specific book in the works of Aristotle, and it was a book on First Philosophy. (The assumption that the word means "beyond physics" is misleading) Metaphysics is the branch of philosophy concerned with the study of "first principles" and "being" (ontology). In other words, Metaphysics is the study of the most general aspects of reality, such as substance, identity, the nature of the mind, and free will.

Logic

Logic (from Classical Greek λόγος (logos), originally meaning the word, or what is spoken, but coming to mean thought or reason) is most often said to be the study of arguments, although the exact definition of logic is a matter of controversy amongst philosophers (see below). However the subject is grounded, the task of the logician is the same: to advance an account of valid and fallacious inference to allow one to distinguish good from bad arguments

Ethics

Ethics is a general term for what is often described as the "science (study) of morality". In philosophy, ethical behavior is that which is "good" or "right." The Western tradition of ethics is sometimes called moral philosophy.

There are lots of other smaller branches as well so have included the link for your information.

http://en.wikibooks.org/wiki/Introduction_to_Philosophy:The_Branches_of_Philosop...