The "room and pillar" method is a mining technique used to extract minerals, particularly in underground operations. In this method, large rooms are created by removing the mineral, while pillars of untouched material are left to support the mine's roof. This design helps prevent collapses and maintains stability in the mining area. This technique is commonly used for mining resources like coal and gypsum. The size and spacing of the pillars can vary based on the type of material being mined and the geological conditions. Overall, room and pillar mining is an effective way to balance resource extraction with safety.