Man has lived on the earth for many thousands of years. He has reached an advanced stage of civilization after having passed through many stages. From primitive origins he made slow progress over a long and difficult road. About six thousand years ago, in the valleys of the Tigris and Euphrates rivers in southwestern Asia, and in the valley of the Nile in northeastern Africa, out civilization had its beginnings. By means of tools, and by the development of various institutions, mankind has made progress.
The people in these sections learned many things. They learned how to write, how to use metals and fire, how to make clothing, and how to build ships, and by various means they spread their knowledge to other parts of the world. The civilization which developed in these river valleys is usually referred to as the Western civilization. Another civilization which developed early is that of China, usually referred to as the Eastern or Asian civilization. This also is an important civilization, but it did not spread like that of the West.