Corner bead is metal, plastic, or paper-faced strips that reinforce corners, protecting these relatively vulnerable areas. Corner bead also gives walls a clean edge that can be sharp or rounded, and when installed level and square, provides a professional look to the drywall job. When corner bead is exposed or out of square, it demonstrates poor workmanship and decreases the overall quality of the home. Exposed corner bead results from poor application practices that make it impossible to apply enough joint compound to properly cover the bead. Metal and plastic corner bead typically have to be installed using fasteners. In contrast, paper-faced corner bead doesn't need fasteners; instead, it's installed with joint compound, which eliminates the possibility of nail pops.