Ancient Indian metallurgists made major contributions to the metallurgical history of the world. Archaeological excavations have shown that the Harappans were master craftsmen and had knowledge of copper metallurgy. They even manufactured bronze by mixing copper and tin. While the Harappans belonged to the Bronze Age, their successors belonged to the Iron Age. India produced highly advanced types of iron-forged iron, wrought iron and cast iron.
While numerals had been used earlier, Aryabhata now invented a special symbol for zero. This system of counting was adapted by the Arabs and then spread to Europe. It continues to be in use throughout the world.
Ayurveda is a well-known system of health science that was developed in ancient India. The two famous practitioners of Ayurveda in ancient India were Charaka and Susruta. Charaka Samhita, written by Charaka is a remarkable book on medicine. In his treatise, Susruta Samhita, Sushruta speaks about elaborate surgical procedures.
Paper was invented in China about 1900 years ago, by a man named Cai Lun. He beat plant fibers, cloth, rope and the bark of trees. He soaked these in water, and then pressed, drained and dried the pulp to create paper. Even today, handmade paper is made through a similar process.
The technique of making paper was a closely guarded secret for centuries. It reached Korea about 1400 years ago, and spread to Japan soon after. It was known in Baghadad about 1800 years ago. From Baghadad it spread to Europe, Africa, and other parts of Asia including the subcontinent.