A fish hook, or fishhook, is a device for catching fish either by impaling them in the mouth or, more rarely, by snagging the body of the fish. Fish hooks have been employed for centuries by fishermen to catch fresh and saltwater fish. Fish hooks are normally attached to some form of line or lure device which connects the caught fish to the fisherman. There is an enormous variety of fish hooks in the world of fishing. Sizes, designs, shapes, and materials are all variable depending on the intended purpose of the fish hook.