The document discusses various techniques for punching and forming sheet metal, including using a gripper line to avoid curling, using a relieved stripper and die to minimize curling, and using a "heel" to prevent side loads in off-center applications. It also describes several techniques that can be done in a single hit, such as piercing and embossing, triple piercing and extruding down, and pre-piercing, extruding, and embossing. Additionally, it mentions progressive punching and forming where each hit finishes a part in two to three progressive hits.