What materials work best to start a fire?

Different fires require different extinguishing agents. Fire extinguishers are labeled as A, B, C, Dor a combination of these. Class A is for things that leave an ash like wood, paper, cloth etc. Water can be used on these. Class B is for things that boil. Gas, oil, some chemicals. You should never use water on these because the burning liquids will spread on the surface of the water and cause more problems. Also NEVER put water on a hot grease fire! The water will boil instantly and send hot grease flying everywhere including on you. CO2 and Cry Chemical extinguishers should be used on Class B. Class C is for things that char from electrical fires. In an electrical fire it's the insulation around the wires that is burning. You can guess why you should never use water on an electrical fire. Electrocution can occur. Once the power company has shut off the power then you can use water or CO2. Class D fires are for metals that burn like magnesium. These are found mostly on aircraft but we're finding them more and more in normal day usage. Dry chemical is best but not great. Water can aggravate the burning metal sending molten burning metal flying. Burning metals? Best leave the area. I'm a volunteer fireman and most fires should be left to trained firefighters. Remember to change the batteries in your smoke detectors. They do save life.