A fire exists because of the chemical reaction of oxygen, heat and fuel. A fire extinguisher works on the concept of keeping these four elements separate. There are different types of fire extinguishers based on the materials being used inside the cylinders. Water & foam, carbon dioxide, dry chemical, wet chemical, clean agent, dry powder, water mist and cartridge-operated dry chemical are some of the fire extinguisher types. The portable fire extinguisher can be only used when the fire is small and can be contained. These are kept handy at fire points in places like petrol pumps, buildings, factories, hospitals, schools, public places, transportation, corridors of hotels and workstations.