Apple Express Fax/Modem - Manual (Page 175)

port The point of connection, usually a physical connector, between a
computer and a peripheral device, another computer, or a network.
protocol An agreement between computers about the form and content of the
information they exchange.
protocol negotiation The process of reaching agreement between computers
about the form and content of the data they exchange.
PSTN Public Switched Telephone Network.
pulse An abrupt and relatively short change in voltage, either positive or
negative, resulting in the conveyance of data in a circuit.
R
register A location in a computer or peripheral processor where an item of
information, such as a byte, is held and modified under program control.
remote computer A computer other than your Macintosh, but connected to it,
either directly or through your modem and telephone lines. A remote
computer can be at any distance from your computer, from right beside it to
thousands of miles away.
RJ-11 The modular phone jacks and receptacles for telephone equipment
used in the United States and Canada.
RS-232-C A physical and electrical interface between computers, terminals,
modems, and communications lines. A standard developed by the Electronics
Industries Association (see serial interface connection).
163 G L O S S A R Y