The most common type of fire extinguisher is the portable fire extinguisher: manageable and usable by an only person, they are suitable to be quickly used on the first phase of fire. There are also wheeled fire extinguishers, that need at least two operators, but can extinguish fully developed fires on which a portable fire extinguisher can do little or nothing. In every public place the presence of at least one fire extinguisher is compulsory.
The amount of necessary fire extinguishers and their type are calculated on the extension of the areas and the risk assessment of the place. It is necessary to see what kind of fuels are inside the area to evaluate which kind of fire extinguisher should be taken. A fire extinguisher that is effective on a wood fire could be not effective on a kitchen fire, while a fire extinguisher successfully used on a fire generated by cloth can damage an electrical apparatus.
Usually, fires are divided into classes, based on their fuel, and one should look at the fire rating of a fire extinguisher before choosing it. First class, class A, includes every fire caused by solid fuels, with the exception of metals, second class (B) includes all fires caused by liquid fuels, third class (C)  fires are fires caused by gaseous fuels, while fourth (D) includes fires generated by metals, fifth class (F) fires are all fires that might develop in kitchens, that are generated by oils or hydrocarbons. There is a sixth class (E) which includes all fires generated by electrical appliances.
A prompt action with a fire extinguisher on the onset of a fire can avoid huge damages and save lives.