G-3
Glossary
supports data transfer rates of up to 400 Mbps for connecting up to 63 external
devices.
IrDA
(Infrared Data Association)
A group of device vendors, including computer, component and telecommunications,
who have developed a standard for transmitting data via infrared light waves. This
enables you to transfer data from one device to another without any cables.
IRQ
(Interrupt Request Line)
IRQs are hardware lines over which devices can send interrupt signals to the
microprocessor. When you add a new device to a PC, you sometimes need to set its
IRQ number by setting a DIP switch. This specifies which interrupt line the device
may use. IRQ conflicts used to be a common problem when adding expansion boards,
but the Plug-and-Play specification has removed this headache in most cases.
LAN
(Local Area Network)
A computer network that covers a relatively smaller area, such as in a building or an
enterprise. It is made up of servers, workstations, shared resources, a network oper-
ating system and a communications link. These individual PCs and devices on a LAN
are known as “nodes”, and are connected by cables to access data and devices any-
where on the LAN, so that many users can share expensive devices and data.
LED
(Light Emitting Diode)
A semiconductor device that converts electrical energy into light. Since it lights up
(usually red) when electricity is passed through it, it is usually used for the activity
lights on computer’s component, such as disk drivers.
LPT
(Line Printer Terminal)
Logical device name for a line printer; a name reserved by the MS-DOS for up to three
parallel printer ports: LPT1, LPT2, and LPT3. It is frequently used by the OS to
identify a printer.
PCI
(Peripheral Component Interconnect)
A local bus standard developed by Intel that first appeared on PCs in late 1993. PCI
provides “plug and play” capability and allows IRQs to be shared. The PCI controller
can exchange data with the system's CPU either 32 bits or 64 bits at a time.
PCMCIA
Short for
P
ersonal
C
omputer
M
emory
C
ard
I
nternational
A
ssociation
, PCMCIA is an
