In Geiger-Muller counter detects the radiation produced by radioactive substance at low-pressure gas filled in a Geiger-Muller tube. An inert gas filled Geiger-Muller tube which becomes conductive due to radiation and conduct electricity. This electricity displayed by a needle or lamp and/or audible clicks.
Geiger Muller counter invented in 1908 but still a popular instruments which can be used for measurements in health, industry, physics, geology and other fields due to the capability of making simple electronic circuits. Various form of Geiger-Muller detectors are available like GM-40, GM-10 widely used in different fields.