A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standrad sizes are determined by various wire gauges. The term wire is also used more loosely to refer to a bundle of such strands, as in 'multistranded wire', which is more correctly termed a wire rope in mechanics, or a cable in electricity. Although usually circular in cross-section, wire can be made in square, hexagonal, flattened rectangular, or other cross-sections, either for decorative purposes, or for technical purposes such as high-efficiency voice coil in loudspeakers. Edge-wound coil springs, such as the Slinky toy, are made of special flattened wire. 9V Battery connector is used to hold 9V batteries in one side and on other side wires of connector are pluged in power supply unit to supply power to whole circuit.Generaly we operate our robot in dc power supply. so connected the dc power source vie a dc connector. one part of the connector is connector of the development board and other is connected with the dc power supply. DC power supply have two different connector one is male and another is female, as same type the 9V dc battery connector have also male and female connector which is connected to battery and complete the circuit. Application: Use to connect dc power supply to the development board. Provide a path betwwen dc power supply and passive parts.