1) Define each of the following terms
a) MICROPROCESSOR a A computer with its entire CPU contained on one integrated
b) PIXEL a Short for picture element. A pixel is the smallest logical unit of visual information
c) that can be used to build an image. Pixels are the little squares that can be seen
when a graphics image is enlarged. The more pixels in an image, the better its
c) SECTOR a Disk storage is organized in sectors, which are pie-shaped slices,
and tracks, which are concentric rings.
d) VDU (Visual Display Unit) a A computer terminal with monitor and keyboard.
e) KEYBOARD BUFFER a A memory area that stores keystrokes when a typist is too fast, to
allow the program to catch up.
f) MACHINE CYCLE a The cycle of four steps a computer's central processing unit must
complete each time a machine language instruction is given:
* Fetching the instruction from the main memory
* Decoding it
* Executing the instruction
* Storing the results
g) MODEM a A peripheral input/output device.
h) SVGA (Super Video Graphic Array) a A type of video display standard for colour
i) CHARACTER MATRIX a An arrangement of pixels that is used to display a character.
j) NON-IMPACT PRINTER a A printer that prints without striking the paper (EX: laser
printer or an inkjet printer).
k) FORMATTING A DISK a Dividing a disk into tracks and sectors.
l) ROM (Read Only Memory) a Memory that can be read but not changed. Read-only
memory is non-volatile storage; it holds its contents even
when the power is turned off. Data is placed in ROM only
once, and stays there permanently.
m) RAM (Random Access Memory) a The working memory of the computer. RAM is the
memory used for storing data temporarily while working
on it, running application programs, etc.
n) CD-ROM (Compact Disc Read-Only Memory) a An optical disk that is physically the
same as an audio CD, but contains computer data.
o) AUXILLARY STORAGE a Disk drives, hard disk, floppy disk, CD-ROM.
p) RESOLUTION a number of dots per square inch required to produce a high-quality image
in printing or on a computer display screen.
q) DATA FLOW a Transfer of data.
s) CLOCK SPEED a The clock rate of a computer is determined by the frequency of vibration
of a quartz crystal which sends pulses to the CPU.
t) VIRTUAL MEMORY a A way of using disk storage space to make the computer work as if
it had more memory. When a file or program is too big for the
computer to work with in its memory, part of the data is stored on
u) KILOBYTE (k, KB, Kb; also Kbyte or K-byte) a A unit of measurement used for
computer file sizes.
v) UPC a Universal Product Code. The bar code commonly found on products in retail stores,
which identifies each product and makes it easy for the cashier to ring up its price.
The code is read into the computer by passing it over a scanner.
2) The components of a microcomputer system are:
A‚A· Input/Output device
A‚A· CPU which consists of ALU & CU
A‚A· Data Bus