There's a lot going on when you strike a match. A match head is made of a number of ingredients, including potassium chlorate, sulfur and powdered glass. The striking surface is made up of sand, powdered glass and red phosphorus. When the match head is dragged along the striking surface, the sand and powdered glass cause friction and heat, which is enough to convert some of the red phosphorous to white phosphorus-a chemical so volatile that it ignites in the air. The heat also breaks down the potassium chlorate in the match head, thereby releasing oxygen that serves as fuel for the fire. The oxygen combines with sulfur and keeps the flame burning. As for the gelatin, it acts as glue to hold everything together in the match head, and also provides extra fuel.