Putting up shelves? A towel bar? A mirror? You'll need more than drywall to hang them on. You'll need the solid backing of a stud (the vertical 2x4s behind finished walls). Here are six ways to find them! Most reliable is the electronic 'stud finder'. It detects changes in density. Pass it over a wall and lights and tones signal a stud. Some locate pipes and wiring, too! ?Low-tech? magnetic finders locate screws and nails, but they also pick up wires, pipes and air ducts that may be nowhere near a stud. ?No-tech? methods include tapping and listening or noting where switches and outlets are installed, as well as eyeball techniques like holding a light close to a wall and looking for nail heads and seams. Finally, there's the ?what-the-heck? method. It involves drilling a hole and either being lucky enough to hit a stud, or (if not), inserting a coat hanger and fishing around inside to find one. The best part? They all work!