Information and Communication Technology
Information & Communication
Information & Communication
Technology
Technology
Data & Information
•
Data can be defined as a
raw of facts
–
Represented with the help of characters like alphabets (A-Z,a-z), digits (0-9)
or special characters(+,-,/,*,<,>,= etc..)
•
Example : Marks of Physics,…
•
Information is the
processed data
on which decisions and actions are
based.
–
Information has some meaningful values to the receiver.
•
Example : Z-Score of Student
•
Data & Information are relative to the source.
–
Marks of Physics is Data relative to the Student
–
Marks of Physics is Data relative to the Examiner
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How to store data in a computer
•
Computer stores data in the form of bit (0 or 1)
–
Both 0 and 1 represents voltage levels.
•
In human readable way it can be referred as files.
•
Many file types or formats.
•
A file format is a standard way that information is encoded for storage in a
computer file
Ex:
Text files
-
doc, docx, txt, rtf, wpd
Data files
-
csv, dat, xml
Audio files
-
aif, m3u, mp3, wav
Video files
-
wmv, mp4, rm, flv
Image files
-
bmp, jpg, png, tiff
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Computing
•
What is Computing
–
Any
goal-oriented activity
with data are called computing.
•
designing ,building, processing, structuring, managing various kinds of information
•
What is computer
–
A computer is an
electronic device
that
manipulates information
, or data
according to
set of instructions
.
–
Set of instructions are called program.
–
That is computer has the ability to retrieve,
process(manipulate) and store data.
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Computer System
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Hardware
•
Physical components
of your computer
such as the system unit (computer),
mouse, keyboard, monitor etc…
•
Basically, hardware means what is
tangible
–
i.e., Something that can be touched and felt.
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Software
•
Collection of
executable programs
with
proper documentation
and
configuration
files
•
That makes the computer work.
•
Held secondary storages (Hard disk, CD-ROM, DVD or on Floppy disk)
•
Loaded (i.e. copied) into the RAM (Random Access Memory), as and when
executing time.
•
Intangible
(cannot be touched and felt) as opposed to hardware.
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liveware
•
People using (attached to) computers.
•
Based on the need for a human, or liveware, to operate the
system using hardware and software.
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Firmware
•
Permanent software programmed into a read-only memory.
•
Software program or set of instructions programmed on a
hardware device.
•
It provides the necessary instructions for how the device
communicates with the other
computer
hardware
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Information & Communication Technology (ICT)
•
Use of computer systems for storing, retrieving, and sending
information.
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Main Parts of a Computer
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Architecture of CPU
Architecture of CPU
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Central Processing Unit
•
The CPU is the brain inside the computer.
•
Main components of CPU
–
Control Unit
•
Directs operation of the processor.
•
Controls communication and co-ordination between input/output devices
–
Arithmetic Logic Unit
•
Digital circuit that performs integer arithmetic and logical operations
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Central Processing Unit…
•
Registers
–
Small amount of memory associated with the CPU
–
It uses to store data to be operated.
–
It also accesses and uses the main memory (RAM - Random Access
Memory) within your computer.
•
CPU and Main Memory are linked together by Buses.
–
Buses contains sets of parallel electrical conducting lines
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System Bus
According to von-neuman architecture there are three buses are used to
communicate between CPU and devices those are
Control bus
Address bus
Data bus
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Computer Storages
Computer Storages
Memory Unit
•
Amount of data
that can be
stored
in the
storage
unit.
•
The
storage
capacity
are expressed in terms of
Bytes
.
BIT
•
A
B
inary dig
IT
is logical 0 & 1
•
Representing a passive or an active state of a component in an electric circuit.
•
Smallest measuring size is Bit
8 bits
= 1 Byte
1024 Bytes
= 1 Kilo Byte
1024 KB
= 1 Mega Byte
1024 MB
= 1 Giga Byte
1024 GB
= 1 Tera Byte
1024 TB
= 1 Peta Byte
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Hierarchy of storage
•
Primary storage
•
Directly accessible to the CPU
•
Ex: RAM
•
Secondary storage
•
It is not directly accessible by the CPU
•
Ex: Hard disk
•
Tertiary storage
•
It involves a robotic mechanism which will mount (insert)
and dismount removable mass storage
•
Off-line storage
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Characteristics of Memory
•
Volatile Memory
•
Requires constant power
to maintain the stored information
•
Loose
its data when the power of the computer is turned off
•
The fastest memory technologies of today are volatile ones
•
Ex: RAM
•
Non-Volatile Memory
•
Will retain the stored information even if it is not constantly supplied with
electric power.
•
It is suitable for long-term storage of information.
•
Ex : Hard Disk
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Random Access Memory (RAM)
•
RAM is the main 'working' memory of the computer.
•
When booting computer, operating system (OS) is loaded from the Hard
disk to the RAM
.
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ROM (Read Only Memory )
•
Special
type of
memory
chip from which existing
software
can be read but not
written to.
–
Ex: ROM-BIOS chip, which contains read-only software.
•
ROM chip is
programmed
during
manufacture
time
•
Network cards
and
video cards
also contain ROM chips.
•
The
ROM contains
the
program
containing the
basic functions
that a computer
should execute when the
computer
is
started
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RAM vs ROM
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Peripheral device
•
External object that provides input and output for the
computer
•
There are three different types of peripherals
•
Input
•
Output
•
Storage
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Secondary Storage Devices
•
Floppy Disk
•
Hard Disk
•
Magnetic strip
•
SuperDisk
•
Tape cassette
•
Zip diskette
•
Flash
•
Memory card
•
Memory stick
•
SSD
•
Blu-ray disc
•
CD-ROM disc
•
CD-R and CD-
RW disc
•
DVD(-R,+R, -
RW,+RW) disc
•
Cloud storage
•
Network
media
•
OMR
•
Punch card
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Floppy Disk
•
Thin magnetic-coated disk contained in a flexible or semi-rigid protective jacket.
•
Data is stored in tracks and sectors.
•
Double sided high density 3.5" disks can hold 1.44 Mb of data.
•
Once data is stored on a floppy disk it can be 'write protected' by clicking a tab on
the disk.
–
This prevents any new data being stored or any old data being erased.
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Hard Disk
•
Concentric circles on the magnetized surface of
the magnetic disks are known as Tracks
•
The tracks on the disk surface are divided into
invisible segments known as Sectors
•
Each sector stores a fixed amount of
user-accessible data
•
512 bytes for hard drives
2048 bytes for CD & DVD ROMs
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Solid state drive(SSD) VS hard drives(HDD)
•
SSD hard drive has no moving parts
–
less chance of breakage
•
SSD hard drive uses flash memory can store and access data much faster.
•
less power consumption
•
Easy to install
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Magnetic tape
•
A magnetically thin coated piece of plastic wrapped around
wheels capable of storing data.
•
Tape is much less expensive than other storage mediums
•
it is a much slower solution that was typically only used for
backup
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Optical Disk
•
Metallic disk that uses a laser beam for reading and writing.
•
There are Four kinds of Optical Disk:
1.
CD-ROM (compact disc read-only memory)
•
Cannot be written on or erased by user (read-only).
2.
CD-R (CD-recordable) or WORM (write once, read many)
•
Can be written to one time only
•
After writing to the disk it cannot be erased by users but can be
read many times without deterioration.
3.
Erasable optical disks
Can be written and erased and reused.
Two basic types:
a.
CD-RW (compact disk re-writeable)
b.
MO (magnetic optical).
4.
DVD(digital versatile disk)
similar to CDs. Have a greater capacity of 4.7 gigabytes.
5.
Blue Ray Disk
Blu-ray beat out HD DVD in the high-definition disc format
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Pen Drives(flash drives)
•
Very high capacity portable devices
•
It can be plugged directly into the USB port
•
Present day pen drives which are about thumb size have gigabytes of
memory
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Memory card
•
Alternatively referred to as a flash memory card.
•
Used to store photos, videos, or other data in electronic
devices
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Cloud computing
•
Services
provided over a network by a
collection
of
remote
servers
.
•
This abstract "cloud" of computers provides
massive, distributed storage and processing
power
–
Can be accessed by any Internet-connected device
running a web browser.
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Network Storage Media
Media is any audio, video, images or text, used on a computer network, like
the Internet.
It almost always requires
a computer to send and receive
a community of people to create and consume the content.
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OMR(Optical Mark Reading )
•
Process of gathering information from human beings by recognizing
marks on a document.
•
Accomplished by using a hardware device (scanner) that detects a
reflection or limited light transmittance on or through piece of paper.
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Punch card
•
Punch card containing several
punched holes that were punched
by hand or machine to represent
data.
•
These cards allowed to store and
access information by entering the
card into the computer.
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Memory Hierarchy
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Memory Hierarchy
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Input Devices
Input Devices
Input Devices
Input Devices
•
Any device used to provide data and control signals to the
Computer
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Mouse
•
A
Mouse
is a palm-sized device
•
Used to control the movement of an object on the computer
screen called a mouse
Cursor
, or pointer.
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Touch pad
•
Device for pointing (controlling input positioning) on a
computer display screen.
•
Alternative to the
Mouse
.
•
Originally incorporated in laptop computers,
•
Also being made for use with desktop computers.
•
Works by sensing the user's finger movement and downward
pressure
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Keyboard
•
The most common way of entering information into a
computer.
•
Number of different types of keyboards
,
including those
specially designed to use with Microsoft Windows.
•
Normally we use “
QWERTY”
keyboard.
•
"The name "
QWERTY
" for our computer keyboard comes from
the first six letters in the top alphabet row.
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Typing(alphanumeric) keys
Function Keys
Control keys
Keyboard…
Scanner
•
A scanner is a device that can read text or images printed on paper and translate the
information into a form the computer can use.
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Digital Camera vs Web Camera
•
Digital camera –
–
Stores images digitally.
–
Once a picture has been taken,
•
it can be transfer to a computer system
•
then edit with a graphics program and printed.
•
Web Camera
–
A video camera, usually attached directly to a computer
–
Takes digital images and transmits them over the
Internet.
–
Widely use for chat trough internet.
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Microphone
•
Converts sound into an
electrical
voltage wave or signals.
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Output Devices
Output Devices
Output Devices
Output Devices
•
Any
device
used to send data from a computer to
another
device
or user.
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Monitor
•
Monitor is
visually interface
with the computer
•
Mainly there are two types of Monitors
–
CRT Monitor
–
LCD Monitor
–
LED Monitor
•
Visual Display Units(VDU)
display
images
and
text
•
Those are made up of
small blocks
of
coloured
light
called
pixels
.
•
The
resolution
of the screen
improves
as the
number
of
pixels
is increased.
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CRT Monitors
CRT
stands for
C
athode
R
ay
T
ube.
The monitor tube is a glass vacuum tube
one end having an electron gun
Electron gun projects three beams
(
red
,
green
, and
blue
)
Display surface coated with phosphors.
When the electron beam strike the coating
it glows with the particular color
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LCD Monitors
•
LCD
stands for
L
iquid
C
rystal
D
isplay
•
Used in digital watches and many portable computers.
•
Low power consumption when considering to the CRT
monitors.
•
Also it has excellent text contrast than CRT.
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LED Monitors
•
An LED display is a flat panel display,
•
Uses an array of light-emitting diodes as pixels for a video
display.
•
capable of providing general illumination in addition to visual
display.
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Ink-jets (bubble-jets) printers
•
Tiny drops
of
ink
onto a page to create an image.
•
Capable of producing
high quality print
which almost matches
the quality of a laser printer.
•
Has a
resolution
of
300 dots per inch
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Laser printers
•
very fast
, and the
supply
cartridges
work long time.
•
Color laser printers
use the same toner-based printing as ( B/W) laser
printers,
–
But that they combine four different toner colors.
•
Color laser printers can also be used as a
regular black
and
white laser
printer
.
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Impact (Dot-matrix) printers
•
Use a set of closely spaced pins and a ribbon to printing.
•
Impact the page to print a character, much like a typewriter.
–
Commonly used for printing invoices, purchase orders, shipping
forms, labels, and other multi-part forms.
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Thermal Printers
•
more quietly
and usually
faster
than
impact dot matrix
printers.
•
They are also smaller, lighter and consume less power, making
them ideal for portable and retail applications.
Commercial applications
•
filling station pumps
•
point of sale systems
•
voucher printers in slot machines
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Plotters
Large-scale printers that are
very accurate
at
reproducing
line
drawings
.
Commonly used for
technical drawings
such as
engineering
drawings
or
architectural blueprints
.
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Headphone
•
A pair of small loudspeakers, or less commonly a single speaker,
•
Held close to a user's ears and connected to a signal source
–
such as an audio amplifier, radio, CD player or portable media player.
•
They are also known as
stereophones
and
headsets.
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Speakers
•
Output of Sounds
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Multimedia Projector
•
At its most basic, a multimedia projector simply projects an image on a
screen.
•
Multimedia projectors can be configured to project a
•
Computer's video signal
•
Outputs from DVD players
•
Direct connections from cable and satellite systems.
•
Designed for almost every application, level of quality, and size of
audience.
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Input Output ports and connectors
•
Ports
–
used to connect external
devices to the computer
•
Connectors
–
cable used to connect the
external device to the
computer through the port
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Types of ports
•
Serial
•
Parallel
•
Universal Serial Bus
•
PS-2
•
Infrared
•
Bluetooth
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Serial ports
•
Transfer data serially a bit in or out one at a time
•
Takes longer time
•
Necessary to send a start bit before each byte of data and stop bit after
each byte of data
•
Often known as communication(COM) port or RS232C port
•
Come in the form of 9-pin or 25-pin male connector
•
Used to plug devices like Keyboard, Mouse or modem
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Parallel port
•
Can send or receive 8-bits at a time
•
Transmits data parallel
•
Comes with 25-pin female connector
•
Used to connect Printers, CD writers, Hard Disks
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USB port
•
Generally used for flash drives, scanners, cameras
•
Now even for mouse, keyboard, printers, etc..
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PS2 port
•
Generally used for mouse, keyboard, printers, etc..
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Infrared Port (IR Port)
•
Sends and receives IR signals
•
Involves a transceiver- transmitter & receiver
•
Short distance
•
Used in TV remotes, Music systems, etc..
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Bluetooth
•
Wireless protocol used to exchange data from fixed and mobile
devices
•
Uses radio frequency
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Types of Software
Types of Software
Software
•
Collection of executable programs with proper documentation
and configuration files
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Types of Software
•
System Software
–
Controls the operations of a computer and the other types of software
that runs on the computer.
•
Ex: operating system, device drivers, programming languages, compilers,
assemblers ,translators and
editors, and debuggers
•
Application Software
–
Type of program that you use once the operating system has been
loaded.
–
Programs designed to perform specific tasks
–
Application software may be of two types.
•
Packaged Software
•
Custom-madeSoftware
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Application software
•
Packaged Software
–
Programs prewritten by professional programmers that are typically
offered for sale.
•
Word-processing applications
•
Spreadsheet applications
•
Database applications
•
Presentation applications
•
Custom-made software
–
Programs written for a specific purpose and for a specific organization
•
Banking system
•
Student Registration System
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Utility Software
–
Carries out all the day to day tasks in maintaining a computer system
and its data files.
–
Ex: screensaver, virus checker, and system tools like disk defragmenter.
–
Certain utility programs are usually bundled along with the operating
system.
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What is an operating System?
•
Software program that enables the computer hardware to
communicate and operate with other software.
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•
It is loaded into the main memory when the computer is
switched on.
LOAD OS TO RAM
Operating Systems….
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Operating Systems….
•
The operating system does the followings on a computer:
–
Controls a Computer’s Hardware
–
Runs a Computer’s Programs
–
Organizes Files
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•
A part of the OS remains in the main memory until the computer
is turned off.
Operating Systems….
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Types of User Interfaces
•
User interfaces let user communicate with the computer.
•
There are two types of them,
–
Command Line Interface (CLI)
–
Graphical User Interface (GUI)
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An Example of a CLI
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Operating System….
•
Command Line Interface(CLI).
–
Users have to use keyboard commands to use the OS.
–
The user has to remember the commands.
–
At the beginning all the OS were running in CLI mode.
–
Even today some OSs give CLI as a part of their system tools.
–
Examples : MS DOS, Linux, UNIX, etc.
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An Example of a GUI
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Operating System….
•
Graphical User Interface (GUI).
–
Contains graphics and icons and is commonly navigated by using a
computer mouse and can be used to invoke commands.
–
The GUI was first used on Apple Macintosh Computers
–
The GUI is very easy to learn and use i.e. user friendly.
–
Many of the modern operating systems come with GUIs
Example :
Windows 3.1 , windows 95 , windows 98, windows ME , windows NT,
Windows 2000, Windows XP(Home/Professional),Windows-8,
Windows-10
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Operating System….
•
Some operating systems support both GUI and CLI.
•
Example : linux
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Hardware
OS
Applications
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Hardware
OS
Applications
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Exploring the realms of information and communication technology, this content delves into the definitions of data and information, how data is stored in computers, the basics of computing, the components of a computer system, and the distinction between hardware and software. It provides insights into the fundamental concepts underlying modern technology and its applications in today's digital world.
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Presentation Transcript
Information & Communication Technology
Data & Information Data can be defined as a raw of facts Represented with the help of characters like alphabets (A-Z,a-z), digits (0-9) or special characters(+,-,/,*,<,>,= etc..) Example : Marks of Physics, Information is the processed data on which decisions and actions are based. Information has some meaningful values to the receiver. Example : Z-Score of Student Data & Information are relative to the source. Marks of Physics is Data relative to the Student Marks of Physics is Data relative to the Examiner 9/19/2024 Information Technology Center, University of Peradeniya 2
How to store data in a computer Computer stores data in the form of bit (0 or 1) Both 0 and 1 represents voltage levels. In human readable way it can be referred as files. Many file types or formats. A file format is a standard way that information is encoded for storage in a computer file Ex: Text files - doc, docx, txt, rtf, wpd Data files - csv, dat, xml Audio files - aif, m3u, mp3, wav Video files - wmv, mp4, rm, flv Image files - bmp, jpg, png, tiff 9/19/2024 Information Technology Center, University of Peradeniya 3
Computing What is Computing Any goal-oriented activity with data are called computing. designing ,building, processing, structuring, managing various kinds of information What is computer A computer is an electronic device that manipulates information, or data according to set of instructions. Set of instructions are called program. That is computer has the ability to retrieve, process(manipulate) and store data. 9/19/2024 Information Technology Center, University of Peradeniya 4
Computer System Computer System Hardware Software Liveware Firmware 9/19/2024 Information Technology Center, University of Peradeniya 5
Hardware Physical components of your computer such as the system unit (computer), mouse, keyboard, monitor etc Basically, hardware means what is tangible i.e., Something that can be touched and felt. 9/19/2024 Information Technology Center, University of Peradeniya 6
Software Collection of executable programs with proper documentation and configuration files That makes the computer work. Held secondary storages (Hard disk, CD-ROM, DVD or on Floppy disk) Loaded (i.e. copied) into the RAM (Random Access Memory), as and when executing time. Intangible (cannot be touched and felt) as opposed to hardware. 9/19/2024 Information Technology Center, University of Peradeniya 7
liveware People using (attached to) computers. Based on the need for a human, or liveware, to operate the system using hardware and software. 9/19/2024 Information Technology Center, University of Peradeniya 8
Firmware Permanent software programmed into a read-only memory. Software program or set of instructions programmed on a hardware device. It provides the necessary instructions for how the device communicates with the other computer hardware 9/19/2024 Information Technology Center, University of Peradeniya 9
Information & Communication Technology (ICT) Use of computer systems for storing, retrieving, and sending information. 9/19/2024 Information Technology Center, University of Peradeniya 10
Main Parts of a Computer 9/19/2024 Information Technology Center, University of Peradeniya 11
Architecture of CPU 9/19/2024 Information Technology Center, University of Peradeniya 12
Central Processing Unit The CPU is the brain inside the computer. Main components of CPU Control Unit Directs operation of the processor. Controls communication and co-ordination between input/output devices Arithmetic Logic Unit Digital circuit that performs integer arithmetic and logical operations 9/19/2024 Information Technology Center, University of Peradeniya 13
Central Processing Unit Registers Small amount of memory associated with the CPU It uses to store data to be operated. It also accesses and uses the main memory (RAM - Random Access Memory) within your computer. CPU and Main Memory are linked together by Buses. Buses contains sets of parallel electrical conducting lines 9/19/2024 Information Technology Center, University of Peradeniya 14
System Bus According to von-neuman architecture there are three buses are used to communicate between CPU and devices those are Control bus Address bus Data bus 9/19/2024 Information Technology Center, University of Peradeniya 15
Memory Unit Amount of data that can be stored in the storage unit. The storagecapacity are expressed in terms of Bytes. BIT A Binary digIT is logical 0 & 1 Representing a passive or an active state of a component in an electric circuit. Smallest measuring size is Bit 8 bits = 1 Byte 1024 Bytes = 1 Kilo Byte 1024 KB = 1 Mega Byte 1024 MB = 1 Giga Byte 1024 GB = 1 Tera Byte 1024 TB = 1 Peta Byte 9/19/2024 Information Technology Center, University of Peradeniya 17
Hierarchy of storage Primary storage Directly accessible to the CPU Ex: RAM Secondary storage It is not directly accessible by the CPU Ex: Hard disk Tertiary storage It involves a robotic mechanism which will mount (insert) and dismount removable mass storage Off-line storage 9/19/2024 Information Technology Center, University of Peradeniya 18
Characteristics of Memory Volatile Memory Requires constant power to maintain the stored information Loose its data when the power of the computer is turned off The fastest memory technologies of today are volatile ones Ex: RAM Non-Volatile Memory Will retain the stored information even if it is not constantly supplied with electric power. It is suitable for long-term storage of information. Ex : Hard Disk 9/19/2024 Information Technology Center, University of Peradeniya 19
Random Access Memory (RAM) RAM is the main 'working' memory of the computer. When booting computer, operating system (OS) is loaded from the Hard disk to the RAM. 9/19/2024 Information Technology Center, University of Peradeniya 20
ROM (Read Only Memory ) Special type of memory chip from which existing software can be read but not written to. Ex: ROM-BIOS chip, which contains read-only software. ROM chip is programmed during manufacturetime Network cards and video cards also contain ROM chips. The ROM contains the program containing the basic functions that a computer should execute when the computer is started 9/19/2024 Information Technology Center, University of Peradeniya 21
RAM vs ROM RAM ROM Temporary memory Permanent memory Volatile memory- contents are lost when power is off Read and Write memory Non-volatile memory- contents are not erased when power is off Read only memory Working memory Used to store startup instructions- booting instructions 9/19/2024 Information Technology Center, University of Peradeniya 22
Peripheral device External object that provides input and output for the computer There are three different types of peripherals Input Output Storage 9/19/2024 Information Technology Center, University of Peradeniya 23
Secondary Storage Devices Secondary Storage Devices Flash memory Online and cloud Paper storage Magnetic Optical Floppy Disk Hard Disk Magnetic strip SuperDisk Tape cassette Zip diskette OMR Punch card Blu-ray disc CD-ROM disc CD-R and CD- RW disc DVD(-R,+R, - RW,+RW) disc Flash Memory card Memory stick SSD Cloud storage Network media 9/19/2024 Information Technology Center, University of Peradeniya 24
Floppy Disk Thin magnetic-coated disk contained in a flexible or semi-rigid protective jacket. Data is stored in tracks and sectors. Double sided high density 3.5" disks can hold 1.44 Mb of data. Once data is stored on a floppy disk it can be 'write protected' by clicking a tab on the disk. This prevents any new data being stored or any old data being erased. 9/19/2024 Information Technology Center, University of Peradeniya 25
Hard Disk Concentric circles on the magnetized surface of the magnetic disks are known as Tracks The tracks on the disk surface are divided into invisible segments known as Sectors Each sector stores a fixed amount of user-accessible data 512 bytes for hard drives 2048 bytes for CD & DVD ROMs 9/19/2024 Information Technology Center, University of Peradeniya 26
Solid state drive(SSD) VS hard drives(HDD) SSD hard drive has no moving parts less chance of breakage SSD hard drive uses flash memory can store and access data much faster. less power consumption Easy to install 9/19/2024 Information Technology Center, University of Peradeniya 27
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Magnetic tape A magnetically thin coated piece of plastic wrapped around wheels capable of storing data. Tape is much less expensive than other storage mediums it is a much slower solution that was typically only used for backup 9/19/2024 Information Technology Center, University of Peradeniya 29
Optical Disk Metallic disk that uses a laser beam for reading and writing. There are Four kinds of Optical Disk: 1. CD-ROM (compact disc read-only memory) Cannot be written on or erased by user (read-only). 2. CD-R (CD-recordable) or WORM (write once, read many) Can be written to one time only After writing to the disk it cannot be erased by users but can be read many times without deterioration. 3. Erasable optical disks Can be written and erased and reused. Two basic types: a. CD-RW (compact disk re-writeable) b. MO (magnetic optical). 4. DVD(digital versatile disk) similar to CDs. Have a greater capacity of 4.7 gigabytes. 5. Blue Ray Disk Blu-ray beat out HD DVD in the high-definition disc format 9/19/2024 Information Technology Center, University of Peradeniya 30
Pen Drives(flash drives) Very high capacity portable devices It can be plugged directly into the USB port Present day pen drives which are about thumb size have gigabytes of memory 9/19/2024 Information Technology Center, University of Peradeniya 31
Memory card Alternatively referred to as a flash memory card. Used to store photos, videos, or other data in electronic devices 9/19/2024 Information Technology Center, University of Peradeniya 32
Cloud computing Services provided over a network by a collection of remoteservers. This abstract "cloud" of computers provides massive, distributed storage and processing power Can be accessed by any Internet-connected device running a web browser. 9/19/2024 Information Technology Center, University of Peradeniya 33
Network Storage Media Media is any audio, video, images or text, used on a computer network, like the Internet. It almost always requires a computer to send and receive a community of people to create and consume the content. 9/19/2024 Information Technology Center, University of Peradeniya 34
OMR(Optical Mark Reading ) Process of gathering information from human beings by recognizing marks on a document. Accomplished by using a hardware device (scanner) that detects a reflection or limited light transmittance on or through piece of paper. 9/19/2024 Information Technology Center, University of Peradeniya 35
Punch card Punch card containing several punched holes that were punched by hand or machine to represent data. These cards allowed to store and access information by entering the card into the computer. 9/19/2024 Information Technology Center, University of Peradeniya 36
Memory Hierarchy 9/19/2024 Information Technology Center, University of Peradeniya 37
Memory Hierarchy 9/19/2024 Information Technology Center, University of Peradeniya 38
Input Devices Any device used to provide data and control signals to the Computer 9/19/2024 Information Technology Center, University of Peradeniya 40
Mouse A Mouse is a palm-sized device Used to control the movement of an object on the computer screen called a mouse Cursor, or pointer. 9/19/2024 Information Technology Center, University of Peradeniya 41
Touch pad Device for pointing (controlling input positioning) on a computer display screen. Alternative to the Mouse. Originally incorporated in laptop computers, Also being made for use with desktop computers. Works by sensing the user's finger movement and downward pressure 9/19/2024 Information Technology Center, University of Peradeniya 42
Keyboard The most common way of entering information into a computer. Number of different types of keyboards, including those specially designed to use with Microsoft Windows. Normally we use QWERTY keyboard. "The name "QWERTY" for our computer keyboard comes from the first six letters in the top alphabet row. 9/19/2024 Information Technology Center, University of Peradeniya 43
Keyboard Typing(alphanumeric) keys Indicator Lights Function Keys Indicator Lights Function Keys Numeric Key Pad Numeric Key Pad Navigation Keys Control keys Navigation Keys Control keys
Scanner A scanner is a device that can read text or images printed on paper and translate the information into a form the computer can use. 9/19/2024 Information Technology Center, University of Peradeniya 45
Digital Camera vs Web Camera Digital camera Stores images digitally. Once a picture has been taken, it can be transfer to a computer system then edit with a graphics program and printed. Web Camera A video camera, usually attached directly to a computer Takes digital images and transmits them over the Internet. Widely use for chat trough internet. 9/19/2024 Information Technology Center, University of Peradeniya 46
Microphone Converts sound into an electrical voltage wave or signals. 9/19/2024 Information Technology Center, University of Peradeniya 47
Output Devices Any device used to send data from a computer to another device or user. 9/19/2024 Information Technology Center, University of Peradeniya 49
Monitor Monitor is visually interface with the computer Mainly there are two types of Monitors CRT Monitor LCD Monitor LED Monitor Visual Display Units(VDU) display images and text Those are made up of small blocks of colouredlight called pixels. The resolution of the screen improves as the numberofpixels is increased. 9/19/2024 Information Technology Center, University of Peradeniya 50
