computer

1. Introduction to IT
MBA
IMS University of Peshawar

2. Course Objectives

Computer is one of the most advanced and fast growing technologies
of the world. Each and every day a lot of improvement is emerging in
both Software and Hardware of the computer.
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In response to this trend this course has been designed.
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It focuses on brief Introduction to Computers History and Types
of computer, the Basics Concepts of Computer Software,
Hardware and Input/Output Device.
Basic aspect of Information Technology, Social Impacts of
Information Technology and Policies.
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3. Week-1

Introduction
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Introduction to Computer Application
Computer
Information Technology
Organization of Computer
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4. Computer
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The word computer comes from the Latin word “computa” which means
“to calculate”.
A computer is normally considered as calculating machine that can
perform arithmetic operation at a very high speed.
An electronic device which is capable of performing series of arithmetic
and logical operations at a very high speed is called computer.
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It is not only a machine which perform different functions on numeric
data but today more than 80% work perform by computer is non
numeric in nature.
Nowadays computer is used for multiple purposes.
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5. Computer (Cont’d)

So what will be the more elaborate definition of computer??
Computer is an electronic device which takes certain input (Data),
manipulate that input (Process), store it in memory or storage devices
and then gives the desired results (Output).
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All computer processing requires data, which is a collection of raw
facts, figures and symbols, such as numbers, words, images, video and
sound, given to the computer during the input phase.
Computers manipulate data to create information with the help of
CPU.
Information is data that is organized, meaningful, and useful.
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6. Computer (Cont’d)
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Memory is an area of computer which holds data that is
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Waiting to be processed, Storing or output
The information can also be put in computer storage for future use.
During the output Phase, the information that has been created is put
into some form, at output devices.
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7. Computer Organization
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8. Information Technology

First you have to understand the differences between science,
engineering & technology.
Science is a systematic & specialized way of thinking. A scientist thinks &
makes principles & hypothesis.
hypothesis
Engineering means the practical implementation of principles & hypothesis
for the welfare of human beings with the help of machines. At first he
makes drawings on the basis of principles, and then take it to real world
for use.
Technology always deals with OPTIMIZATION (MAXIMUM GAIN WITH
MINIMUM EFFORTS) with the help of newer supports like computers &
transfer machines.
The aim of IT is to make our information more profitable by making it
recently & attractive.
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9. Information Technology

(Cont’d)
Information Technology is the application of Computers towards organizing
and efficient retrieval/reporting of information.
Information Technology refers to the creation, gathering, processing,
storing, protecting, presenting and dissemination of information using ,
hardware, software and telecommunication technology.
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10. Introduction to Computer Hardware

Introduction to Computer Hardware

System Unit
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Motherboard
 BIOS
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Basic Unit of Measurement
Processor
Memory
 RAM
 ROM
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Storage Devices
 Magnetic Storage Devices
 Formatting
 Optical Storage Devices
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11. Hardware
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The physical components of a computer is called Hardware.
The physical (electronic and mechanical) parts of a computer is called
Hardware.
Hardware is one that is tangible.
The storage devices (Hard disk, CD’s etc.,), mouse, keyboard CPU and
display devices (Monitor) are Hardware.
The hardware devices attached to the computer are called peripheral
devices.
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12. System Unit
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The System Unit is a case which is just like a box made up of a metal
or plastic. This casing actually contain the electronic components of a
computer used to process data.
The casing is some time called Chassis, that protect the internal
electronic components from damage.
The most important component of this System box is Mother Board.
All the components are then installed on this Mother Board.
System Unit consist of the following devices: Mother Board
 Processor
 Memory
 Disk systems
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13. System Unit (Cont’d)
power supply
drive bays
processor
memory
ports
sound card
network card
modem card
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video card

14. Mother Board

It is the main circuit board of the system unit.
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It is the centralized platform where all the hardware components of a
computer are connected.
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Many electronic components are attached to the mother board, others
are built-in on it.
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Each and every Motherboard has a small battery cell.
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It gives to Motherboard a small amount of power to remember the
settings such as hardware configurations, date and time etc
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15. System Unit (Cont’d)
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16. System Unit (Cont’d)
adapter cards
processor chip
memory chips
memory slots
Expansion
slots for
adapter cards
motherboard
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17. Mother Board (Cont’d)
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BIOS is kind of software which holds the most important data for
machine.
It informs the PC about the compatibility of Motherboard with
different hardware components such as CPU etc…
It is the most important component which resides in the ROM (Read
Only Memory) of the Motherboard.
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18. Basic Units Of Measurement

BIT
 BInary digiT
 Smallest unit of measurement
 Two possible values 0 & 1
ON
or
OFF
BYTE
8 bits
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19. Basic Units Of Measurement
(Processor And Memory Speed)
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Millisecond (ms) – a thousandth of a second (1/1,000 = 10 -3)
Microsecond (µs) - a millionth of a second (1/1,000,000 = 10 -6)
Nanosecond (ns) – a billionth of a second (1/1,000,000,000 = 10-9)
Large Units Of Measurement (Memory, Storage)
Note: powers of two are used because computer memory and storage
are based on the basic unit (bit).
Kilobyte (KB) – a thousand bytes (1,024 = 210)
Megabyte (MB) -1,024 KB - a million (1,048,576 = 220)
Gigabyte (GB) –1,024 MB - a billion (1,073,741,824 = 230)
Terabyte (TB) – a trillion (1,099,511,627,776 = 240)
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20. Processor
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The Processor is also called Central Processing Unit (CPU).
All the CPUs looks very similar, but they are different in the way,
they have different numbers of pins and different layouts.
“Central Processing Unit (CPU) is an electronic device that interprets and
carries out the instructions that operates the computer.
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The processor significantly impact over all computing power & manages
most of computer operations.
Some computer manufacturer use the term Microprocessor which
refers to a personal computer chip.
Most PC’s today use processors manufactured by IntEL, AMD etc..
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21. Processor (Cont’d)
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22. Processor (Cont’d)

The combination of Arithmetic Logic Unit and Control Unit is called as
Central Processing Unit (CPU). OR The two main parts of CPU are ALU
& CU.
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23. Processor (Cont’d)
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Registers are the part of the processor, not a part of memory or
storage devices.
It contain different type of registers, each with a specific storage
functions. E.g. General purpose registers used for arithmetic
operations & data movement. AX, BX, CX, DX
Register function includes
 Storing the location from where an instruction is fetched,
 Storing the location while the CU encode/decode it,
 Storing data while the ALU compute it and
 Storing the results after a calculation.
Today, most PCs have 32-bit registers, mean the CPU can process
four bytes of data at one time.
Register sizes are rapidly growing to 64 bits.
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24. Multi-Core Processor
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A Multi-Core Processor is a processing system composed of two or more
independent cores. The cores are typically integrated onto a single integrated
circuit die(known as a chip multiprocessor or CMP).
Core
Basic processing area of a computer processor
Die
A die in the context of integrated circuits is a small block of semiconducting
material, on which a given functional circuit is fabricated.
A medium-scale integrated circuit die
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25. Multi-Core Processor
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(Cont’d)
A Dual-Core and Core 2 Duo Processor contains two cores, and a Quad-Core
Processor contains four cores.
A Multi-core processor implements multiprocessing in a single physical
package.
Cores in a multi-core device coupled together tightly.
Cores may or may not share caches.
Dual Core and Core 2 Duo’s are both dual core processor.
Core2 duo only takes advantage because
The Core 2 Duo has the same L2 cache but it has more cache size than a Dual
core. However,
There are architectural changes to the silicon that give the Core 2 Duo more
sophisticated processing.
The single- and dual-core models are single-die, whereas the quad-core models
comprise two dies, each containing two cores, packaged in a multi-chip module.
Differences between Dual Core, Core 2 Duo, Core i3, Core i5, Core i7.

Cache memory and Core’s
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26. Memory
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The electronic component which provides storage capability to a computer is
called Memory.
Memory contains one or more sets of
Seat #2B4
Seat #2B3
chips that store data/program
instructions need processing,
either temporarily or permanently.
All the computers which are used
today needs memory or storage capability.
The CPU accesses each location
in memory by using a unique number,
called the memory address.
Each byte stored
in unique location
called an address,
similar to addresses
on a passenger train
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27. Memory
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The are two types of Memory
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Random Access Memory
Read Only Memory
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(Cont’d)

28. Random Access Memory
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RAM is also called volatile memory and Keeps the information for a
shorter period of time because RAM Lost information if powered off
or the computer is shutdown.
RAM store data or instructions, the computer then uses these
instructions to perform any processing work.
The contents of RAM change rapidly and often.
Typical ranges from Mega Bytes to Giga Bytes
Random Access means direct access to any part of memory
Memory chips that can be
read from and written
to by processor
Also called
main memory
or primary
storage
Most RAM is
volatile, it is lost
when computer’s
power is
turned off
The more RAM a
computer has, the
faster it responds
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29. How do program instructions transfer in and out of RAM?
Step 1. When you start the computer, certain
RAM
Operating system
instructions
operating system files load into RAM from the hard
disk. The operating system displays the user interface
on the screen.
Operating system
interface
Step 2. When you start a word processing program,
Word processing
program instructions
the program’s instructions load into RAM from the
hard disk. The word processing program, along with
the Web Browser and certain operating system
instructions are in RAM. The word processing
program window is displayed on the screen.
Word processing
program window
RAM
Web browser program
instructions are removed
from RAM
Step 3. When you quit a program, such as the Web
browser, its program instructions are removed from
RAM. The Web browser no longer is displayed on the
screen.
Web browser window
no longer is displayed
on desktop
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30. Where does Memory Reside?
dual inline memory module
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Resides on small circuit
board called memory
module
Memory slots on
motherboard hold
memory modules
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memory chip
memory slot

31. Random Access Memory
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(Cont’d)
The amount of RAM in a PC has a direct affect on the system's
speed.
The more RAM a PC has, the more program instructions and data can
be held in memory, which is faster than storage on disk.
More RAM = Better Performance !
There are two types of RAM
 Dynamic RAM
 Static RAM
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32. Random Access Memory

(Cont’d)
Dynamic RAM
 Dynamic RAM (DRAM) chips must be recharged with electricity
very frequently, or they will lose their contents.
 DRAM is further divided in two types
 SDRAM
 DDR-SDRAM
 It achieves twice the bandwidth of the preceding single data rate SDRAM

Static RAM
 Static RAM (SRAM) does not need to be recharged as often as
DRAM, and can hold its contents longer.
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33. Random Access Memory
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DDR SDRAM
DDR 2 SDRAM
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(Cont’d)

34. Read Only Memory
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ROM is non-volatile memory.
The kind of memory is generally programmed by manufacturer.
It contains information that is permanently stored.
The contents of ROM are set during manufacturing process. Most of
the ROMs are special purpose memories.
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Example of ROM is BIOS (Basic Input Output System).
TYPES OF ROM
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PROM (Programmable Read Only Memory)
Normally ROM’s are not writable but PROM’s are writable. Data can be
written to PROM’s using special devices.
Data once written cannot be removed. Ultraviolet Rays are used to write
data in PROM’s.
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35. Read Only Memory (Cont’d)
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EEPROM (Electronically Erasable Programmable Read Only
Memory)
EEPROM needs an electric impulse to write or erase data.
It has all the features of EPROM except the difference of
erasing technique i.e. it uses electric impulse instead of ultraviolet
light rays for erasing.
Therefore erasing can be achieved through the use of keyboard
commands without removing the chip physically from the computer.
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36. Cache Memory
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Cache memory is high-speed memory that holds the most recent data
and instructions that have been loaded by the CPU.
Cache is located directly on the CPU or between the CPU and RAM,
making it faster than normal RAM.
 CPU-resident cache is called Level-1 (L1) cache.
 L1 cache usually has a very small capacity, ranging from 8 KB to 128
KB. The most common size is 128 KB.
Level-2 (L2) cache.
 L2 cache is slower then L1 cache but has much larger capacity,
ranging from 64 KB to 4 MB.
The amount of cache memory has a tremendous impact on the
computer's speed.
When the processor needs an instruction or data, it searches memory in
this order, L1 cache, then L2 cache, then RAM.
If the instructions or data is not found in memory then it must search a
slower speed storage medium such as a hard disk, compact disc etc.
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37. Storage Devices
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Storage devices holds data, instructions & information for future use.
Every computer uses storage devices to holds software, specifically
system software & application software's.
It is also called Secondary Storage or Auxiliary Storage Devices.
Example of storage media are
Magnetic Storage Devices
 Hard Disk Drive,
 Floppy Disk
Optical Discs:
 CD-R, CD-RW, DVD
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38. Hard Disks
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Auxiliary storage is a hard disk.
Hard disks use multiple platters, stacked on a spindle. or
A hard disk consists of one or more rigid metal plates coated with a metal
oxide material that allows data to be magnetically recorded on the surface of
the platters.
Each platter has two read/write heads, one for each side.
The hard disk platters spin at a high rate of speed, typically 5400 to 7200
RPM.
Storage capacities of hard disks for personal computers range from 10 GB to
320 GB (TB is possible but rare).
Read/write heads
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39. Formatting
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Formatting is the process of preparing a disk for reading and writing.
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Before a magnetic disk can be used, it must be formatted—a process that
maps the disk's surface and determines how data will be stored.
During formatting, the drive creates circular tracks around the disk's
surface, then divides each track into sectors.
The OS organizes sectors into groups, called clusters, then tracks each
file's location according to the clusters it occupies.
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40. Hard Disk
Sectors
each track is divided into pieshaped wedges
Cluster
two or more
sectors combined

Tracks
data is recorded in circular
bands
The hard disks available today is called an optically assisted hard drives. It
combines optical technology with magnetic media, which have potential
storage capacity up to 500 GB. Abdus Salam

41. Optical Storage Devices
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An optical disc is a high-capacity storage medium. An optical drive uses
reflected light to read data.
To store data, the disc's metal surface is covered with tiny dents (pits) and
flat spots (lands), which cause light to be reflected differently.
When an optical drive shines light into a pit, the light cannot be reflected
back. This represents a bit value of 0 (off).
A land reflects light back to its source, representing a bit value of 1 (on).
1
0
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42. Optical Storage Devices (Cont’d)
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CD's (Compact Disc) 700 MB storage
 CD-ROM (read only)
 CD-R: (Record) to a CD
 CD-RW: Can write and erase CD to reuse it (Re-Writable)
 DVD (Digital Video Disc)
A compact disk (CD), also called an optical disc, is a flat round, portable
storage medium that is usually 4.75 inch in diameter.
A CD-ROM (read only memory), is a compact disc that used the same laser
technology as audio CDs for recording music.
In addition it can contain other types of data such as text, graphics, and
video.
The capacity of a CD-ROM is 650 MB of data, about 70 minutes of audio.
Once data is written to a standard CD-ROM disk, the data cannot be
altered or overwritten.
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43. Optical Storage Devices (Cont’d)
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A CD-Recordable (CD-R) drive lets you record your own CDs, but data
cannot be overwritten once it is recorded to the disk.
A CD-Rewritable (CD-RW) drive lets you record a CD, then write new
data over the already recorded data.
A variation of CD-ROM is called Digital Video Disk Read-Only Memory
(DVD-ROM), and is being used in place of CD-ROM in many newer PCs.
Standard DVD disks store up to 4.7 GB of data—enough to store an
entire movie.
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44. Optical Storage Devices (Cont’d)
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Dual-layer DVD disks can store up to 9.4 GB.
DVD disks can store so much data because of sophisticated data
compression technologies.
At a glance, a DVD-ROM look like a CD-ROM, the size and shape are
similar, but
DVD-ROM store data, instructions & information in a slightly
different manner and thus it achieves high storage capacity.
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HD-DVDs can store 15 GB

Blue-Ray DVDs can store 25 GB
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