When I take a picture of the sun it develops as a black spot. Is my film faulty?

If you take images of a scene that has a very bright element such as the sun, it will overexpose that part of the film. This will result in a little black mark shown on the film. This is normal, but to avoid, do not shoot directly into the sun or bright light source. If you really want to capture the sun in your image or similar, you can try holding some sunglasses over the lens whilst shooting as this can help reduce the chance of overexposure.