The Terai ( Nepali: तराई Hindi: तराइ ) is a plain landscape Madhesh region of Nepal and the plain land region in Bangladesh, Bhutan and India that lies in south of the outer foothills of the Himalaya, the Siwalik Hills, and north of the Indo-Gangetic Plain of the Ganges, Brahmaputra and their tributaries.
The Stone Age is divided into three different periods.
- Paleolithic or Old Stone Age
- Mesolithic or Middle Stone Age
- Neolithic or New Stone Age