A match lights when you strike it because the striking surface contains a material that can undergo a chemical reaction with the chemicals in the match head. The match head contains a mixture of chemicals, including an oxidizing agent (usually potassium chlorate) and a reducing agent (usually sulfur). When the match is struck against the striking surface, the friction generates enough heat to ignite the chemicals in the head of the match. This chemical reaction produces heat, light, and a flame that can be used to light a candle or start a fire.