Smoke is usually produced when something is burned. Smoke is made up of bits of soot, and lots of other gases like Carbon dioxide. Smoke can have a variety of things that come from what the fire is burning and where the smoke is coming from. Smoke gets its color from the gases and materials that are inside of it. Smoke can be bad for your lungs if you inhale it for too long because the particles of smoke can get stuck in your lungs. Smoke actually fuels fires because the tiny pieces of soot and the gases can be flammable. That is why firefighters try to get smoke out of a building to put the fire out.