Apple Express Fax/Modem - Manual (Page 174)

O
odd parity Use of an extra bit set to 0 or 1 as necessary to make the total
number of 1 bits in a character an odd number. For example, the 7-bit ASCII
code for the letter A (1000001) has two 1 bits; for odd parity, the transmitting
device appends an eighth bit equal to 1 (11000001) so that the total number of
1 bits remains odd. The receiving device can count 1 bits as a way of
checking for transmission errors.
off-hook Your equipment takes control of the telephone line (picks up the
receiver).
on-hook Your equipment releases (hangs up) the telephone line.
on-line state The state the modem is in when data is being exchanged with
another computer over the telephone line. Contrast with terminal mode.
originate mode The connection mode in which the modem places a call.
outline fonts Characters described as a series of mathematical shapes. Can be
automatically scaled to any dimension with no loss of definition.
P
parity A method of detecting errors in data transmission. Due to higher-
quality telephone lines and higher-level error control protocols, many host
computers don’t support parity.
parity bit A check bit appended to an array of binary digits to make the sum
of all the binary digits, including the check bit, always odd or always even.
parity error Absence of the correct parity bit in a received character.
PBX Private Branch Exchange. An automatic switchboard for handling large
concentrations of telephones (usually digital extensions).
peripheral device A device, such as a video monitor, disk drive, printer, or
modem, used in conjunction with a computer. Often (but not necessarily)
physically separate from the computer and connected to it by wires, cables, or
some other form of interface.
162 G L O S S A R Y