The importance of metals, writing, wheel and the plough is given below:

Metals: The archeologists have found metals such as copper, bronze, gold and silver.

1. Copper was used for making tools, ornament, weapons and vessels.

2. Bronze as produced by mixing Tin with Copper. It was a strong metal used for making tools, weapons, statues and ornament.

3. Gold and silver were considered precious metals and used for making ornaments and vessels.

Writings: The seals found in Harappan civilization had the earliest known writings. These writings were generally found on seals. Writings are important in order to learn about this civilization.

Wheels: People of Harappan civilizations travelled great distances to fetch raw materials and precious metals. Carts with wheels helped them in transporting goods and materials to their location.

Plough: Plough is a device which is used to turn soils in the fields for planting. Plough helped the farmers to prepare their fields easily. Hence plough helped in agriculture.