Jig heads are fishing hooks with metal or lead secured around the hook's eyelet. The added weight creates a jig head, which helps it cast further and sink more effectively. Jig heads work with nearly all types of sport fish, and it's most important to pick a jig with the right hook size for your target species and the right size weight to help you reach them most efficiently.
Decide the weight of your jig by the depth, current, or wind you are fishing, and the jig's hook size should be relative to the type of fish you're going after and the lure or live bait you plan to pair with your jig.