(1) Artificial digging wells: Before 1521.
(2) Manpower impact drill: From 1521 to 1835, it was accomplished by manpower, sand drums, special drills, suspension ropes, and beams.
(3) Mechanical drilling (drilling): From 1859 to 1901, rock was broken by mechanical impact, and rock breaking and clear rock were alternated.
(4) Rotary Drilling: Developed in 1901, rotary drilling is driven by the rotation of the drill bit to break down the rock at the bottom of the well during the rotation process, while circulating the drilling fluid to clean the bottom of the well. Rotary drilling is divided into rotary drilling, downhole power drilling, and top-driven rotary drilling.