USB is "Universal Serial Bus”. It is a plug and play interface. It transmit electronic information from a source to a destination and vice versa. The most common interface used in today's computers, which can be used to connect printers, scanners, keyboard, mice, game controllers, digital cameras, external hard drives and flash drives. It increases the speed of data transmission between external devices. It is used to transfer data between computers with at least one USB port but it is mainly used for charging devices