Harappans were responsible for several significant technological innovations such as standardization, transport, trade, crafts, and agriculture.
The Indus Valley or Harappan civilization was the largest of the four ancient urban civilizations and is considered one of the best with respect to its organization and infrastructure. The remnants of the Indus Valley Civilization were discovered first in the earlier part of the 20th century when the land survey before the digging of canal revealed the presence of the striking ruins of the ancient city known as Harappa or Harappan situated alongside the Indus River. Thereafter, the excavations at Mohenjodaro, Chanhudaro, Dholavira, and Kalibangan sites revealed urban settlements that belong to the period 2500–1900 BCE. Harappans were responsible for several significant technological innovations such as standardization, transport, trade, crafts, and agriculture. It is likely that farmers advocated cereal production on the fertile plains of the Indus Valley and exploited the sea for coastal trade. Such export contacts included Coca, copper, Ti, pottery, and beads. In return, traders from Mesopotamia imported gold, silver, beads of semi-precious stones, and jewelry. Not only did Harappaners gain confidence in the use of metal and stone to make jewelry, they were also adept at the creation of small stone weights. Small stone weights in the form of cubes, rectangular prisms, disk-shaped, cylindrical, and perforated objects were found in the Indus Valley. The precise statement of these weights helps to regulate trade and the measurement of money.