(3) Diodes are kinds of device that allow current flow only in one direction in circuits.Thus, only half of the cycles of alternating current can pass from the diodes. One can easily convert alternating current into the direct current with this device. Most of the electrical devices in our homes work with alternating current,TV, Washing machines, hair drier etc. One can convert AC to DC with transformer which decreases the amount of voltage,and one can use diodes in his circuits.