UART stands for Universal Asynchronous Receiver/Transmitter controller which is the key component of serial communications subsystems in many applications. The UART takes parallel bytes of data and transmits them serially. At the destination, a second UART reassembles the bits into complete bytes. Serial transmission is commonly used for non-networked communication between computers, terminals and other devices. UARTs are also commonly used as interfaces for communication modules such as Bluetooth and GPRS.