Philosophy:

Philosophy is called as ''The Mother of All Sciences''. Philosophy teaches criticism and systematic thinking about the fundamental issues of life. It is the study of logical research of the fundamental problems of life and world.
Philosophy is one of the oldest branches of knowledge. The word 'Philosophy' was first used by Greek thinkers and mathematician named Pithagoras.

The word is used at first on the sixth episode BC. Pythagoras did not consider himself wise, but he was the lover of wisdom.

Philosophy is a section of knowledge that should give how should life lead (ethics); What kind of object exists and what is their nature (metaphysics); What is the meaning of real knowledge and what are the principles of reasoning (logic); Discuss these issues.
According to Will Durant, ''it is precisely the combination of knowledge learning on five subjects of Philosophy. These are logic, metaphysics, ethics, politics and aesthetics.'' But I think, epistemology, logic, metaphysics, ethics, politics, aesthetics and Philosophy of language are the most important branches of Philosophy.

References:
Some information I have taken from internet.