Computers and Communication

orangesvetElectronics - Devices

Nov 8, 2013 (3 years and 10 months ago)

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Computers and Communication

Computers and Communication


Computer Technology is responsible for
causing great leaps forward in
communication technology.


Computers are all around us and come in
sizes from a single chip to a whole room
full of equipment.


Computer applications include online
communication, word processing, desktop
publishing and computer aided design.

From Micros to Supercomputers


Computers surround us even though we don’t
always know that they are there.


To better understand the sizes and
capabilities, computers are put into
categories.


These categories are microprocessors,
microcomputers, minicomputers, mainframes
and supercomputers.

Microprocessors


Integrated Circuits that
perform and control
arithmetic functions.


Embedded in appliances like
ovens and washing
machines.


Used for single applications
like controlling the time of
an on
-
off cycle.


Microcomputers


Have microprocessor chips
at their heart.


Personal computers found
in homes and offices.


Have a collection of
integrated circuits with one
microprocessor chip.


Microcomputers memories
can be very small or very
large.

Mainframe Computers


Large computers used by
large companies, government
agencies and universities for
their administrative work.


Could include making
payroll cheques, records of
employees, tracking orders,
warehouse inventory etc.


Mainframes can perform
millions of instructions per
second and often have
billions of bytes of memory
attached to them.

Supercomputers


Fastest and Largest
Computers


Often used for
research, analyzing
satellite data or other
very large problems.


Can perform several
billions operations at
one time.


Very expensive to
purchase and operate.

Information Exchange


In order for the
information that a
computer produces
to be useful, it has to
be exchanged with
people or other
machines outside the
computer.


This exchange is
called input/output.

Input


Input is to provide information
to a computer.


The device you are most
familiar with is the keyboard.


People can issue instructions or
provide raw data using the
keyboard.


Other forms of input include a
mouse, floppy disk, CD
-
Rom,
Scanners etc.


Disks or CD’s can contain a
program or data which the
computer will load into its
main memory.

Computer Output


Output can come in many forms


Most common is the monitor or
CRT screen (Cathode Ray Tube)
which Converts electronic
signals to visual images.


Printers records the computers
output on paper. Called a hard
copy.


Plotters use one or more pens
whose position is controlled by a
computer to create drawings on
paper


Data Communications


Output of computers can be
sent to other computers using
a modem.


This kind of information
exchange is called data
communications.


Modems send computer data
over standard telephone lines
using sequences of tones to
represent the bits of
information to be sent.

Online Communication


You can have access to a
lot of information by
dialing a telephone
number that connects
your home computer to a
mainframe computer.


This is referred to as
being online, or surfing
the net.


The internet can provide
news, weather, sports,
banking, travel services
and home shopping.

Electronic Mail


Instead of sending letters through the mail,
you can use a computer to send electronic
messages.


In large companies, e
-
mail is a popular way
to provide communication among their
employees.

Word Processing


Word processing software has
made the job of typists easier.


Has features that
“Typewriters” do not.


Text can be checked for
proper spelling, paragraphs
can be moved from one place
to another, columns and lines
can be rearranged.

Computer
-
Aided Design


Computers are changing the
way people do technical
drawing.


With Computer
-
Aided design
(CAD) systems, drafters can
create, change and store more
complex drawings than ever
before.


Computer Aided Drafting has
become one of the most
important tools used by
engineers, drafters and
designers.

Desktop Publishing


Computers are now able to
produce whole pages with
words, headlines and
illustrations.


Using special software,
desktop publishing lets
you arrange copy and
graphics on a computer
screen just as you would
like it to appear on paper.

All Purpose Tool


Computer software provides the computer
with specific instructions which direct it to
do certain tasks.


Since computer programs can be changed to
suit a particular application, a computer can
be thought of a general purpose tool.