This isn't about how fast you can take pictures. It's about how much light you need to get clear images.
Film speed indicates sensitivity to light.
It's expressed as the ISO number you see on your film boxes. So if the speed of your film is ISO 200, you should set 200 on the ASA dial of your camera or meter. Now you do. So look for the ISO number on your film cartons and choose the speed appropriate for the conditions where you'll be taking pictures or choose Kodak MAX for great pictures across a wide range of picture-taking conditions. Automatic speed adjustments Automatic cameras automatically set the proper film speed by reading a code on the film called the DX code.