SINKERS:  There are several types of weights or sinkers, most are made of lead, but new ones are often made of steel or synthetic materials.  You should avoid putting lead weights in your mouth or licking your fingers after handling them.  The reason for using a weight is to help get your bait down near the bottom where many fish (especially catfish) live and feed..  They are commonly used with live (earthworms, crickets, shrimp) bait or natural baits (cheese balls, chicken necks, pieces of hot dogs) and seldom used with artificial baits (plastic worms, spinner baits etc.).  For some fish, letting the weight pull the bait all the way to the bottom is okay.  Another common use of weights, a special type called slip sinkers or bullet weights is for when you are fishing with rubber worms or other soft-plastic lures that are rigged either Carolina-style or Texas-style.