Artisanal and small-scale mining (ASM) is a blanket term for a wide variety of types of small mining that range from manual subsistence mining using simple tools to vocational mining that is semi-mechanised involving light machinery such as generators, water pumps, and small motorized mills, through to organised mechanised mining that employs industrial equipment such as excavators and bull dozers. ASM involves miners who may or may not be officially employed. Although there can be large numbers of miners working at a mining site, they typically work in small teams according to a customary system of organisation that includes a manager, skilled and unskilled labour.