3. AN OVERVIEW OF THE
COMPUTER SYSTEM
AN OVERVIEW OF THE
COMPUTER SYSTEM
4. WHAT IS A COMPUTER
A computer is an
electronic, digital
and programmable
device that can
store, retrieve and
process data.
WHAT IS A COMPUTER
5. The two principal characteristics of a
computer are:
• It responds to a specific set of instructions in a
well‐defined manner.
• It can execute a prerecorded list of instruction
(a program).
The two principal characteristics of a
It responds to a specific set of instructions in a
It can execute a prerecorded list of instruction
6. FOUR BASIC FUNCTIONS OF A
COMPUTER
• INPUT – information entered into the computer
or program for processing, as from any input
device.
• PROCESS – the manipulation and transformation
of data into some something useful.
FOUR BASIC FUNCTIONS OF A
COMPUTER
information entered into the computer
or program for processing, as from any input
the manipulation and transformation
of data into some something useful.
7. FOUR BASIC FUNCTIONS OF A
COMPUTER
• OUTPUT – the result of the manipulated and
processed data.
• STORAGE – computer can save data so that it
can be used at another time.
FOUR BASIC FUNCTIONS OF A
COMPUTER
the result of the manipulated and
computer can save data so that it
can be used at another time.
8.
9. A Complete Computer System
Includes Four Distinct Parts:
• Hardware
• Software
• Data
• Peopleware
A Complete Computer System
Includes Four Distinct Parts:
Hardware
Software
Peopleware
10. HARDWARE
– A computer's hardware consists of electronic
devices; the parts you can see and touch.
– The term "device" refers to any piece of
hardware used by the computer, such as a
keyboard, monitor, modem, mouse, etc.
HARDWARE
A computer's hardware consists of electronic
devices; the parts you can see and touch.
The term "device" refers to any piece of
hardware used by the computer, such as a
keyboard, monitor, modem, mouse, etc.
11. INPUT DEVICES
accept data and instructions
from another computer system
mouse are examples of input
INPUT DEVICES
instructions from the user or
system. The keyboard and
input devices.
12. Two Types of Input Devices
• Keyboard Entry – data
computer through a keyboard
• Direct Entry – a form
require data to be keyed
a keyboard. Direct‐
machine‐readable data
media or feed it directly
CPU.
Two Types of Input Devices
data is inputted to the
keyboard
form of input that does not
keyed by someone sitting at
‐entry devices create
data on paper or magnetic
directly into the computer’s
13. Three Categories of Direct Entry
Devices
1. POINTING DEVICES
Mouse
controls
the
display
Three Categories of Direct Entry
Devices
Mouse ‐ A device that
controls the movement of
the cursor or pointer on a
display screen
14. Three Categories of Direct Entry
Devices
1. POINTING DEVICES
Touch
A type of display screen that
has a touch
transparent panel covering
the screen
Three Categories of Direct Entry
Devices
Touch Screen
A type of display screen that
has a touch‐sensitive
transparent panel covering
the screen
15. Three Categories of Direct Entry
Devices
1. POINTING DEVICES
An input device that utilizes
a light
select objects on a display
screen
Three Categories of Direct Entry
Devices
Light Pen
An input device that utilizes
a light‐sensitive detector to
select objects on a display
screen
16. Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
A device that can read text
or illustrations printed on
paper and translate the
information into a form the
computer can use.
Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
Scanner
A device that can read text
or illustrations printed on
paper and translate the
information into a form the
computer can use.
17. Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
Short for
a device that can send or
receive pictures and text
over a telephone line
Three Categories of Direct Entry
Devices
Fax Machine
Short for facsimile machine,
a device that can send or
receive pictures and text
over a telephone line
18. Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
Bar‐code Reader
The machine‐readable
representation of the
Universal Product Code
(UPC). Bar codes are read
by a scanner that passes
over the code and registers
the UPC.
19. Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
OCR is the mechanical or
electronic translation of
images of handwritten,
typewritten or printed text
(usually captured by a
scanner) into machine
editable text.
Three Categories of Direct Entry
Devices
2. SCANNING DEVICES
Character and Mark
Recognition Device
OCR is the mechanical or
electronic translation of
images of handwritten,
typewritten or printed text
(usually captured by a
scanner) into machine‐
editable text.
20. Three Categories of Direct Entry
Devices
3. VOICE RECOGNITION DEVICES
A device with integrated
person’s speech or voice to
Three Categories of Direct Entry
Devices
3. VOICE RECOGNITION DEVICES
A device with integrated
software that converts
person’s speech or voice to
digital codes
21. OUTPUT DEVICES
return processed data back to the user or to
another computer system.
OUTPUT DEVICES
return processed data back to the user or to
another computer system.
22. MONITOR
Another term for
display screen. The
term monitor,
however, usually
refers to the entire
box, whereas display
screen can mean just
the screen. In
addition, the term
monitor often implies
graphics capabilities.
MONITOR
Another term for
display screen. The
monitor,
however, usually
refers to the entire
box, whereas display
screen can mean just
the screen. In
addition, the term
often implies
graphics capabilities.
24. PRINTER
A device that
prints text or
illustrations on
paper. There are
many different
types of printers.
PRINTER
A device that
prints text or
illustrations on
paper. There are
many different
types of printers..
31. SOFTWARE
– also called programs
sets of instructions for controlling the
computer.
– Some programs exist for the computer's use,
to help it manage its own tasks and devices.
– Other programs exist for the user, and enable
the computer to perform tasks for you, such
as creating documents
SOFTWARE
also called programs – consists of organized
sets of instructions for controlling the
Some programs exist for the computer's use,
to help it manage its own tasks and devices.
Other programs exist for the user, and enable
the computer to perform tasks for you, such
as creating documents
32. DATA
– consists of raw facts, which the computer
can manipulate and process into information
that is useful to people.
– computerized data is digital, meaning that it
has been reduced to digits, or numbers. The
computer stores and reads all data as
numbers.
– although computers use data in digital form,
they convert data into forms that people can
understand, such as text, numerals, sounds,
and images.
DATA
consists of raw facts, which the computer
can manipulate and process into information
that is useful to people.
computerized data is digital, meaning that it
has been reduced to digits, or numbers. The
computer stores and reads all data as
although computers use data in digital form,
they convert data into forms that people can
understand, such as text, numerals, sounds,
33. USER
–
–
USER
people are the
computer's operators, or
users.
some types of
computers can operate
without much
intervention from
people, but personal
computers are designed
specifically for use by
people.
34. COMMUNICATION DEVICES
COMMUNICATION DEVICES
network interface cards) perform both input and
output, allowing computers to share information.
COMMUNICATION DEVICES
COMMUNICATION DEVICES (such as modems and
network interface cards) perform both input and
output, allowing computers to share information.
35. MODEMMODEM
• Short for modulator‐
demodulator.
• A modem is a device or
program that enables a
computer to transmit data
over, for example,
telephone or cable lines.
Computer information is
stored digitally, whereas
information transmitted
over telephone lines is
transmitted in the form of
analog waves. A modem
converts between these
two forms.
36. LAN CardLAN Card
• A communication
device that allows
computers to
communicate with
other computers and
computer peripherals
through a network or
a computer to
computer
connection.
37.
38. Computer Networks
• A network is a group of computers and
associated devices that are connected by
communication facilities.
• is a group of computers that are connected to
each other for the purpose of communication.
Computer Networks
A network is a group of computers and
associated devices that are connected by
communication facilities.
is a group of computers that are connected to
each other for the purpose of communication.
39.
40. Wide Area Network
A type of network which
side and worldwide
microwaves relays and satellites
Wide Area Network
which consists of country
networks, often using
satellites.