Serial communication is basically the transmission or reception of data one bit at a time. Today’s computers generally address data in bytes or some multiple thereof. A bit is basically either a logical 1 or zero. Every character on this page is actually expressed internally as one byte. The serial port is used to convert each byte to a stream of ones and zeros as well as to convert streams of ones and zeroes to bytes. The serial port contains an electronic chip called a Universal Asynchronous Receiver/Transmitter (UART) that actually does the conversion.