A serial port is a computer interface that transmits data one bit at a time. In common use, the term “serial port” refers to ports that use a particular asynchronous protocol. These ports include the RS-232 ports on PCs and many serial ports in embedded systems. Most serial ports are bidirectional: they can both send and receive data. Transmitting one bit at a time might seem inefficient but has advantages, including the ability to use inexpensive cables and small connectors.
