pinhole cameras are cameras but for the lens it is make out of can of coke or KA and with a little hole in it. It also has a little black cover so the light can't get the to the light sensitive paper. When you open the little cover the light can get to it and the paper picks up whats is in its view. The paper is make to of little particles of silver and when it light hits it it changes the colour of the paper when you put it into a mix of certain chemicals.