A press brake is used for bending sheet metal by pressing the sheet or plate between a matching punch / top tool and bottom die or v-block. There are several types of press brakes determined by the type of operation: mechanical, pneumatic, hydraulic and servo-electric. Most press brakes has a backgauge or backstop system used to accurately position a sheet. On the NC and CNC models the backgauge can be programmed to move between bends.