CPU- Central
Processing Unit. The CPU controls the operation of a computer. Units
within the CPU perform arithmetic and logical operations and decode and
execute instructions. In microcomputers, the entire CPU is on a single
chip.
RAM- Random
Access Memory. The working memory of the computer. RAM is the memory used
for storing data temporarily while working on it, running application
programs, etc. "Random access" refers to the fact that any area
of RAM can be accessed directly and immediately, in contrast to other
media such as a magnetic tape where the tape must be wound to the point
where the data is. RAM is called volatile memory; information in RAM will
disappear if the power is switched off before it is saved to disk. There
is also a form of non-volatile RAM, which must be continually energized by
a battery to maintain its content. The most common form of RAM is built
from semiconductor integrated circuits
HARD DRIVE- Hard
disk drive. A disk drive that reads from and writes to a hard disk.
OPTICAL DRIVE A- Digital
Versatile Disc or Digital Video Disc. An optical storage medium which has
greater capacity and bandwidth than a CD. DVDs can be used for multimedia
and data storage. A DVD has the capacity to store a full-length film with
up to 133 minutes of high quality video in MPEG-2 format, plus audio.
KEYBOARD- A
set of keys for computer input, which resembles a typewriter keyboard, but
with a few extra keys for computer commands and usually a numeric keypad
added. The original typewriter keys worked mechanically to make a metal
hammer with a raised, inked type character on it strike a page. On a
computer keyboard, hitting on a key sends an electrical signal to a
microprocessor, which sends a scan code to the computer's basic
input/output system. The BIOS translates the scan code into an ASCII code
that stands for a character, which is read by the operating system or
program so the character appears on the screen.
MOUSE- A
pointing device that is used to move a cursor on the computer screen, and
make various operations possible such as typing, drawing, editing text and
graphics, opening and closing files, and giving other commands. The wire
connecting it to the computer or keyboard looks like a mouse's tail. A
mouse is moved over a flat horizontal surface, usually a rubber mouse pad,
and its position is read by the computer. The original mouse has a button
which the user clicks or holds down to place the cursor; now many models
have more than one button.
OPTICAL DRIVE B- Digital
Versatile Disc or Digital Video Disc. An optical storage medium which has
greater capacity and bandwidth than a CD. DVDs can be used for multimedia
and data storage. A DVD has the capacity to store a full-length film with
up to 133 minutes of high quality video in MPEG-2 format, plus audio
MONITOR- -Also
called a display. A device that displays text and graphics generated by a
computer. Desktop monitors are usually cathode-ray tubes, and laptop
monitors are usually liquid crystal display. A monitor can be monochrome
(black and white) or color. Color monitors may show either digital or
analog color.
NIC-Network
Information Center. An organization that provides
information services to the users of a network
SPEAKERS- Used to
generate sound from the computer system.
VIDEO CARD- Also
called graphics adapter, display adapter, video adapter. A circuit board
that enables a computer to display information on its screen. The
resolution, number of colours, and refresh rate of a monitor is determined
by the kind of video card used, plus the limitations of the monitor
itself.
MOTHER BOARD- The
main circuit board inside a computer, which contains the central
processing unit, the bus, memory sockets, expansion slots, and other
components. Additional boards, called daughter boards, can be plugged into
the motherboard.
CD-ROM-Compact
Disc Read-Only Memory. An optical drive that is physically the same as an
audio CD, but contains computer data. Storage capacity is about 680
megabytes. CD-ROMs are interchangeable between different types of
computers.
MODEM-A
peripheral device that connects computers to each other for sending
communications via the telephone lines. The modem modulates the digital
data of computers into analog signals to send over the telephone lines,
then demodulates back into digital signals to be read by the computer on
the other end; thus the name "modem" for modulator/demodulator.
Modems are used for sending and receiving electronic mail, connecting to
bulletin board systems, and surfing the Internet. There are standards to
ensure that modems made by different manufacturers can communicate with
each other. Modems communicating with each other must use the same speed.
SOUND CARD- An
add-on expansion board that improves a computer's sound quality, and adds
other sound capabilities. A sound card makes it possible to use speakers,
a stereo, and a microphone to record and play sound; some sound cards also
include MIDI.
CASE- The housing that all
computer hardware is kept inside
