Chains are the measuring instrument used in surveying formed by the 100 links of 4mm galvanized mild steel wire. These links are joined by 3 circular or oval wire rings. These rings provide the flexibility to the chains.
Every aspect of the life requires some measuring units. Measurements are used to do the work precisely and accurately. Let it be from kitchen to office, everywhere measurements are used. So as in engineering calculation or measurements holds a very greater role in construction or surveying or any other aspect.
There are various units of measurements such as meters, centimeters, feets, inches, acre, yards and the list goes on. Same as units there are various instrument used in the measurements of any entity. One of the instruments used in measurement are chains.