When we strike a match which is made of sulfur against a hard surface (I don't know what the surface is made of) a flame is produced. That flame can then cause a piece of wood to burn. We can also see the flame. Why? Let me take my best guess since this website likes people to try. Please correct my mistakes. When sulfur strikes the hard surface friction is produced. Friction is essentially atoms bumping up against each other. The electrons of the two different substances rub against each other and since electrons are negative it requires energy to push them close. That energy causes the atoms to jitter more and the more they jitter the more the electrons ascend into a higher orbit. When the electrons ascend into a higher orbit they release a photon, which is the flame that we see. Photons have energy so when a flame from a match made of sulfur comes into contact with wood, the photons are hitting the wood which is mostly carbon, hydrogen and oxygen. As the photons hit the wood they cause the atoms in the woods to excite which causes the electrons surrounding the nucleon to ascend into a higher orbit and release a photon. I guess I would like to know why a piece of wood gets converted into ash when burnt. As the atoms speed up and move faster they gradually break their bonds to the other atoms in the wood. I suppose the atoms still clump together and break away as chunks which is why we can still see ash. But the space between atoms is far greater in wood than in ash.