The discovery of the Indus valley writing has led some scholars to guess that Brahmi was locally developed out of the Indus valley writing system. The modern Bangla alphabet originated from the ancient Indian Brahmi script, which was the oldest and popular script of India. But the Kharoshthi alphabet has not made any contribution to the development of the Bangali alphabet. Besides these, a number of terracotta seals and fragment potsherds have been discovered from Chandraketugarh and Bedachapa in West Bengal, which bear also the Kharoshthi alphabet.
A number of Kusana coins, which have been discovered from Bengal, bear the Kharosthi script. It spread over other parts of India during the Kusana period. But this script was mainly limited in the North-West frontier of India.
The ancient Indians took the Kharosthi alphabet from the Aramaic script. The Kharosthi was written from the right to the left, while the Brahmi left to the right. By virtue of the direction of writing, ancient Indian scripts are divided mainly into two parts, the Brahmi and the Kharoshthi.
