Flow control
Flow control is a mechanism or code that compensates for differences in the flow of data into and out of a communication device such as a computer Modem, network device, or other device that handles data. Flow control is necessary in data communications because it's possible that the sending computer may be faster than the receiving computer and sending the data too fast would result in errors or lost data.
Tip: Don't confuse Flow control with Control Flow.
Also see: Error control, Modem definitions, Software flow control