Which coloured wire is used for earthing?

Basically earthing wire is the safety measure to prevent shocks and device damages. Devices like electric motor, heater, iron and refrigerator use very high amount of current. Whenever there is a leak of electricity/current from these devices, the leaked current reaches the metallic plates of these devices and if we touch them with bare hand we will get a shock. This may cause very harmful damage.

So, to prevent such type of situation there is earthing wire, which basically absorb all the leaked current from the device and dump it to the earth. This dumping of leaked current from the device is very useful as it prevents damage to the device as well as human.