IDE-compatible hard disk drive. SCSI drives operate in the same
way, but use a 68-pin Header. In non-IDE mainboards, the drive
connects to a hard drive host adapter rather than directly to an
expansion slot on the mainboard.
21. Internal Clock: The actual internal operating clock that determines the
electrical frequency of the CPU's power input. The internal clock
is a multiple of the external clock.
22. I/O: I/O device (Input/Output device).
23. IR: (Infrared) The device which allows two computers to The device which
can transfer data to from CPU is called and transfer information by
means of infrared light.
24. ISA: (Industry Standard Architecture) The original PC bus architecture,
which replaced the vague AT bus specification. VO device.
25. Jumper: A short wire or plastic-covered metal block that connects with
two Pins on the mainboard to close a circuit, thereby regulating
electrical flow within a computer.
26. Keylock. Literally a lock on the computer case that connects directly to
the mainboard and disables the keyboard to prevent tampering.
27. LED: (Light Emitting Diode) A semiconductor diode that emits light when
charged. LEDs are used in numerous electronic appliances as readout
displays or on/off lights.
28. MPEG: (Motion Picture Expert Group) The industry standard for
information compression of motion picture.
29. OS: (Operating System) Software that controls and supervises the
operation of a computer and establishes interface between
application programs and the hardware and file system, such as
Unix/Xenix and DOS.
30. Parallel Port: An I/O attachment used to hook up the printer or any
other parallel interface device in which information is transferred
both to and from the computer.
31. PCI: (Peripheral Component Interconnect) A bus standard initiated by
Intel with a bus width of 32 bits. ISA, with only 16 bits, is
slower than PCI.
32. Peripheral: Any hardware device that connects to the computer, such as a
monitor, keyboard, or printer.
33. EnP (Plug and Play): An I/O function allowing the user to change add-on
cards without manually updating the BIOS. When a new peripheral is
plugged in, PnP directs BIOS to automatically detect it and
self-format accordingly.
34. DRAM: Dynamic Random Access Memory) The most common type of computer
memory. DRAM forms the computer's primary workspace and requires
uninterrupted electrical power and periodic charge . Turning off
the computer causes RAM to lose its memory.
35. ROM: (Read Only Memory) A memory chip which, unlike RAM, holds its
content without power input. ROM contains fundamental operating
programs that cannot be changed frequently and are needed by the
computer at power up, such as BIOS. Though basically unalterable.
The content of the Flash ROM can be updated. BIOS manufacturers
which utilize PnP technology allow the computer to update the Flash
ROM BIOS configuration at each boot up depending on how various
hardware is detected.
36. POST: (Power On Self-Test) After the computer is turned on, the ROM BIOS
