 Throughout most of the history of personal computers, data was transferred through serial ports to devices such as modems, terminals, and various peripherals.While such interfaces as Ethernet, FireWire, and USB all send data as a serial stream, the term "serial port" usually identifies hardware compliant to the RS-232 standard or similar and intended to interface with a modem or with a similar communication device.It can also refer to hardware compliant to other standards, such as RS-485 and RS-422, that are often used in industrial settings.