Film was once the only type of photography available. People loaded film into cameras, and the film created a picture when the shutter was opened and the film was exposed to light.
Film cameras were the only type available just a decade or so ago. Now it is nearly impossible to buy a film camera. Nearly all cameras made today are digital.
Film is developed by placing the exposed film into several different chemicals that bring out the image and transferring the image onto paper. When the chemicals have dried, the result is a photograph.