Today's modern definition for lures are that they be made of wood, plastic, rubber, metal, cork, and materials like feathers, animal hair, string, tinsel and others. They could also have any number of moving parts or no moving parts. They can be retrieved fast or slow. Some of the lures can be used alone, or with another lure. In most cases they are manufactured to resemble prey for the fish, but they are sometimes engineered to appeal to a fishes' sense of territory, curiosity or aggression. Most lures are made to look like dying, injured, or fast moving fish.