The earliest period was called Palaeolithic. The word ‘palaeo’ is a Greek word which means ‘old’ and ‘lithos’ means ‘stone’. It means “Palaeolithic” is Old Stone. During this period, stone tools were used by the people and hence, this period is known as “Palaeolithic”. This period extends from 2 million years ago to about 12,000 years ago. This period is divided into Lower, Middle and Upper Palaeolithic. This covers 99% time of human history.