Underground mining is used to access ores and minerals located far beneath the ground when surface mining is not economical. It involves digging into the ground to extract resources. Underground mining is used when the ore deposit is deep, the grade is high enough to mine profitably, or surface mining is not permitted or practical due to issues like nearby forests, rivers, or habitation. There are different methods used for hard rock mining, which involves metals, and soft rock mining, which involves minerals like coal. Accessing the ores requires removing overburden via vertical shafts, declines, or adits, and then excavating levels and stopes. Safety precautions like ventilation, supports, and equipment are needed.