Information Technology

By Md. Monowar Hossain, FCA,CISA,CPFA

CA
Information Technology (IT)
Module-02: Information Technologies
Information (3) Hardware (4) Software (5) Data Resource Management
Technologies (6) Telecommunications and Network (7) Cloud Computing
(8) Mobile Computing (9) Internet of Things
(10) Data Encryption and Encryption-related Techniques

Understand and Identify history, trends, developments in different computer systems; and the major types of technologies
used in peripheral devices for computer input, output, and storage.

Computer 9
Computer hardware includes the physical,
Hardware tangible parts or components of a computer,
such as the cabinet, central processing unit (CPU),
monitor, keyboard, computer data storage, graphic
card, sound card, speakers and motherboard. By
contrast, software is instructions that can be stored
and run by hardware.

Hardware is an essential part of any computer system, and it determines the

performance and capabilities of the device. The different components of
hardware work together to enable the computer system to perform various
tasks, from running programs to displaying images and playing audio and
video.
Hardware can be classified into different categories based on their functions
and applications, such as personal computer hardware, mobile device hardware,
server hardware, and networking hardware. The type of hardware required
depends on the specific needs of the user or organization.
Computer hardware refers to the physical components of a computer system
that can be seen and touched. These components work together to enable the
processing, storage, and retrieval of data. Here are some common types of
computer hardware:

9
https://en.wikipedia.org/wiki/Computer_hardware

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

Central Central Processing Unit (CPU): Also known as the processor, the CPU is the
Processing "brain" of the computer. It performs calculations, executes instructions, and
Unit (CPU) coordinates the activities of other hardware components.

Motherboard Motherboard: The motherboard is the main circuit board that connects and
holds together various components of the computer. It provides the electrical
connections and data pathways between different hardware components.

RAM Random Access Memory (RAM): RAM is the temporary storage area where data
and instructions are stored while the computer is actively running programs. It
provides fast access to data for the CPU and is essential for multitasking and
overall system performance.

HDD/SSD Hard Disk Drive (HDD) or Solid-State Drive (SSD): These are storage devices
used to store data on a long-term basis. HDDs use spinning disks and magnetic
storage to store data, while SSDs use flash memory technology, providing faster
access times and higher data transfer rates.

Graphics Graphics Processing Unit : GPUs are specialized processors designed to handle
Processing graphics-intensive tasks. They are used for rendering images, videos, and 3D
Unit graphics, making them crucial for gaming, video editing, and other visually
demanding applications.

Display Display Monitor: The display monitor is the output device that shows the visual
Monitor output from the computer. Monitors come in various sizes, resolutions, and
types (e.g., LCD, LED, OLED) and allow users to view text, images, and videos

Keyboard and Keyboard and Mouse: These input devices allow users to enter commands and
Mouse interact with the computer. Keyboards are used for typing, while mice or
trackpads are used for pointing, clicking, and navigating on-screen.

Optical Drives Optical Drives: Optical drives, such as CD/DVD drives, allow the computer to
read and write data from optical discs. However, these drives are becoming less
common as digital distribution and cloud storage have become more prevalent.

Networking Networking Hardware: This includes network interface cards (NICs), routers,
Hardware switches, and modems that enable communication and data transfer between
computers and networks.

Power Supply Power Supply Unit (PSU): The PSU supplies electrical power to all the
Unit components of the computer. It converts the alternating current (AC) from the
power outlet into the direct current (DC) required by the computer.

Peripherals Peripherals: Peripherals include devices connected to the computer to provide

additional functionality, such as printers, scanners, external hard drives,
speakers, webcams, and microphones.

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By Md. Monowar Hossain, FCA,CISA,CPFA

Computer
hardware is
designed to
work together,
allowing users
to perform
tasks, run
software
applications,
and store and
retrieve data.
Advances in hardware technology have led to faster processors, increased
storage capacities, improved graphics capabilities, and more efficient power
consumption, enabling the development of powerful and versatile computing
devices.

There are two types of

computer hardware: external
and internal.

External hardware devices

include monitors, keyboards,
printers, and scanners, whereas
internal hardware devices
include motherboards, hard
drives, and RAM.
Computer Computer Systems: End User and Enterprise Computing
Systems
All computers are systems of input, processing, output, storage, and control
components.
End-user computing (EUC) refers to computer systems and platforms that are
meant to allow non-programmers to create working computer applications. It is
a compilation of approaches meant to better involve and integrate end users and
other non-programmers into the world of computing systems development.
History of Brief History of Computer Hardware
Computer Without computers, many technological achievements would not have been
Hardware possible:
Counting with fingers/toes
Blaise Pascal, 1642 – invented the first mechanical adding machine
Herman Hollerith – Hollerith’s Punch Card system to record census data in
late 1880’s; 1911 – merged with competitor to form IBM
ENIAC (Electronic Numerical Integrator and Calculator), 1946 – the world’s
first electronic digital computer
1950’s – Transistors were invented and replaced tubes
1958 – Integrated Circuit (“chip”) was invented
1970’s – 1980’s - Further miniaturization of circuits
Apple Computer and IBM PC

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

Generations The Five Generations of Computers

of Computers 1st Generation: Vacuum Tubes.
2nd Generation: Transistors.
3rd Generation: Integrated Circuits.
4th Generation: Microprocessors.
5th Generation: Artificial Intelligence.

Types of Types of Computer Systems

Computer Computers come in a variety of sizes, shapes, and computing capabilities –
Systems o Mainframes
o Midrange (obsolete due to powerful microcomputers)
o Microcomputers

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By Md. Monowar Hossain, FCA,CISA,CPFA

Mainframe A mainframe
Computer computer, informally
called a mainframe or
big iron, is
a computer used
primarily by large
organizations for critical
applications, bulk data
processing (such as the
census and industry and
consumer statistics,
enterprise resource
planning, and large-scale
transaction processing)

Mainframe Systems - large, fast, and powerful, used for high transaction
processing and complex computations; used by corporations and government
agencies

Microcomputer Microcomputer Systems (Personal Computer)

Systems
The most important category for businesses and consumers, exceeds the power
of many mainframes
o Workstations – support mathematical and graphical demands
o Network Servers – support telecommunications and resource sharing
o Computer Terminals – any device that allows access to a computer
o Network Computers – designed specifically for use with networks and
the Internet; low TCO (total cost of ownership)
o Information Appliances – Web-enabled devices for accessing
information from anywhere – cell phones, PDAs, handheld PCs

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Midrange Midrange Systems - popular as Network Servers; disappearing due to

Systems microcomputers.

Midrange systems are primarily high-end network servers and other types of
servers that can handle the large-scale processing of many business applications.

Supercomputers Supercomputers - extremely powerful, extremely high speeds and massive

numeric computations.
The Next Wave of Computing - mini-supercomputers; connecting all the power
of unused desktops in an organization.
Distributed (Grid) Computing – parallel computing over a network
• Advantages – purchase nodes as a commodity, economies of scale
• Disadvantages – untrustworthy calculations, lack of centralized control

Computer The Computer System Concept

System A computer system is a set of integrated devices that input, output, process, and
Concept store data and information. Computer systems are currently built around at least
one digital processing device.

There are five main

hardware components in
a computer system:
(1) Input,
(2) Processing,
(3) Storage,
(4) Output, and
(5) Communication devices.

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

A computer is a system of hardware devices organized according to the

following system functions:

• Input - The input devices of a computer system include computer

keyboards, touch screens, pens, electronic mice, and optical scanners. They
convert data into electronic form for direct entry or through a
telecommunications network into a computer system.

• Processing - The central processing unit (CPU) is the main processing

component of a computer system. (In microcomputers, it is the main
microprocessor). Conceptually, the circuitry of a CPU can be subdivided into
two major subunits: the arithmetic-logic unit and the control unit.
The electronic circuits (known as registers) of the arithmetic-logic unit
(ALU) perform the arithmetic and logic functions required to execute
software instructions.

• Output - The output devices of a computer system include video display

units, printers, and audio response units. They convert electronic
information produced by the computer system into human-intelligible form
for presentation to end users.

• Storage - The storage function of a computer system takes place in the

storage circuits of the computer’s primary storage unit, or memory,
supported by secondary storage devices such as magnetic disk and
optical disk drives. These devices store data and software instructions
needed for processing. Computer processors may also include storage
circuitry called cache memory for high speed, temporary storage of
instruction and data elements.

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

• Control - The control unit of a CPU is the control component of a computer

system. Its registers and other circuits interpret software instructions and
transmit directions that control the activities of the other components of the
computer system.

Computer A peripheral device is generally defined as any auxiliary device such as

Peripherals: a computer mouse or keyboard, that connects to and works with
Input, the computer in some way. Other examples of peripherals are expansion
Output, and cards, graphics cards, image scanners, tape drives, microphones, loudspeakers,
Storage webcams, and digital cameras.
Technologies
Peripheral – a generic name
for all
• input,
• output, and
• secondary storage
devices not part of
the CPU (basically,
what is connected to
the outside of the
computer)

Input Devices: keyboards, mice, light pens, trackballs, touch screens

Input Technologies -
•
Speech Recognition Systems – understands spoken commands/ words
•
Discrete Speech Recognition – speak each word separately
•
Continuous Speech Recognition – recognizes conversationally-paced speech
•
Speaker-Independent Voice Recognition – understands speech from a voice
it has never heard before
•
Optical Scanning – converts text or graphics to digital input for direct entry
of source documents
•
Other Input Technologies
- Magnetic Stripe – on credit cards
- Smart Cards – contain an embedded chip
- Digital Cameras
- Magnetic Ink Character Recognition (MICR) – used in banking industry

Output Technologies -
Computers provide information in a variety of forms. Video displays and printed
documents have been, and still are, the most common forms of output from
computer systems. Yet other natural and attractive output technologies, such as

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

voice response systems and multimedia output, are increasingly found along
with video displays in business applications.

Video Output - Video displays are the most common type of computer output.
Many desktop computers still rely on video monitors that use a cathode ray
tube (CRT) technology similar to the picture tubes used in home television sets.

The biggest use of liquid crystal displays (LCDs) has been to provide a visual
display capability for portable microcomputers and PDAs.

Printed Output - Printing information on paper is still the most common form
of output after video displays.

Storage Storage Tradeoffs - Data and information must be stored until needed using a
Tradeoffs variety of storage methods.

Storage media cost,

speed, and capacity
trade-offs. Note how cost
increases with faster
access speeds but
decreases with the
increased capacity of
storage media.

Direct and Direct and Sequential Access

Sequential
Access

Sequential Access – All

tape devices are accessed
serially – device must be
read one record at a time
from the data until the
desired data is found.
Direct Access and
Random Access are the
same concept; locate an
address on the storage
device and go directly to
that location for data
access.

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

Semiconductor Semiconductor Memory

Memory

RAM (Random Access Memory) – volatile, may be read and over-written

ROM (Read Only Memory) – non-volatile, may be read but not over-written or
erased.
PROM (Programmable Read-Only Memory) and EPROM (Erasable
Programmable Read-Only Memory) may be reprogrammed.

PROM is a written type of ROM. This memory is written only once by the user
and electrically programmed at that time. EPROM is a type of ROM that can be
written and read optically.
Flash (Jump) Drives – solid-state memory

Computer Computer Storage Fundamentals

Storage Storage capacities – kilobytes (KB), megabytes (MB), gigabytes (GB), terabytes
(TB)

Magnetic Disks
Hard drives are the most common form of secondary
storage
RAID (Redundant Arrays of Independent Disks) Storage –
interconnected groups of hard drives - fast speeds and fault
tolerant (redundant backups)
Magnetic Tape & Optical Disks
Magnetic Tape – slow speeds, but inexpensive for large amounts of
backups
Optical Disks – CD-ROM, CD-R, DVD-R (cannot be erased or re-written);
CD-RW, DVD-RW (may be erased or re-written)

Representing Representing characters in bytes

characters in • Binary Representation – Two-state, on/off, +/-, 0/1
bytes • Bit – Binary digit, 0/1
• Byte – Grouping of bits (typically 8 bits/byte), represents a single character

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By Md. Monowar Hossain, FCA,CISA,CPFA

ASCII – formalized code determining what byte values represent which character

Evolution of Evolution of Computer Systems

Computer A computer is a system of information processing components that perform
Systems input, processing, output, storage, and control functions. Its hardware components
include input and output devices, a central processing unit (CPU), and primary
and secondary storage devices.

Microcomputers are used as personal computers, network computers,

personal digital assistants, technical workstations, and information
appliances.
Midrange systems are increasingly used as powerful network servers and
for many multiuser businesses data processing and scientific applications.
Mainframe computers are larger and more powerful than most midsize
systems. They are usually faster, have more memory capacity, and can
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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

support more network users and peripheral devices. They are designed to
handle the information processing needs of large organizations with high
volumes of transaction processing or with complex computational
problems.
Supercomputers are a special category of extremely powerful mainframe
computer systems designed for massive computational assignments.

Radio Radio Frequency Identification (RFID)

Frequency
RFID – for tagging and identifying mobile objects (store merchandise, postal
Identification
objects, sometimes living organisms); provides information to a reader when
requested.
Passive – no power source, derives power from the reader signal
Active – self-powered, do not need to be close to the reader
RFID Privacy Issues – may be used as spychips; gathers sensitive information
about an individual without consent

Watch the Computer Basics: Inside a computer https://www.youtube.com/watch?v=HB4I2CgkcCo

videos What is Computer System https://www.youtube.com/watch?v=Sd9Djp1txgo

The History of Computer Hardware https://www.youtube.com/watch?v=WU_Xfk3rWvA&t=1s

The History of Computers https://www.youtube.com/watch?v=asgjklztBIc

Types of Computers https://www.youtube.com/watch?v=uD0acIhi8xE

All About Computer Memory https://www.youtube.com/watch?v=aR9yyFzi0Cc

Storage vs. Memory: What's the Difference? https://www.youtube.com/watch?v=H_M--weEzpA

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

CA
Information Technology (MCQ for exam preparation)
Information Technology : Hardware
41. Which of the following components 42. In which year was the first electronic
is responsible for temporarily storing general-purpose computer, ENIAC
data and instructions that are (Electronic Numerical Integrator and
currently being processed by the Computer), completed and unveiled to the
CPU? public?
A) RAM (Random Access A) 1940
Memory) B) 1946
B) ROM (Read-Only Memory) C) 1960
C) GPU (Graphics Processing Unit) D) 1970
D) HDD (Hard Disk Drive)
Ans.A Ans.B
43. Which of the following factors is 44. Which of the following storage
NOT typically considered when technologies offers the fastest access
evaluating the performance of a speed but has the lowest storage capacity?
computer system?
A) Hard Disk Drive (HDD)
A) Processing speed
B) Magnetic Tape
B) Storage capacity
C) Optical Disc
C) Graphics resolution
D) Software compatibility D) Solid-State Drive (SSD)
Ans.C Ans.D
45. Which of the following statements 46. How many bits are required to represent a
best describes the computer systems single character in the ASCII encoding
concept? system?
A) A computer system is a
A) 4 bits
collection of physical
B) 6 bits
components, including
C) 8 bits
hardware and software, working
D) 16 bits
together to perform tasks and
process data.
B) A computer system refers to the Explanation: In the ASCII (American Standard
software programs and applications Code for Information Interchange) encoding
installed on a computer. system, each character is represented using 8
C) A computer system is a network bits. A bit is the smallest unit of information in
of interconnected computers computing, representing either a 0 or a 1. Eight
bits together form a byte. The ASCII encoding
used for communication and
system assigns a unique 8-bit binary code to
data sharing. represent each character, allowing for a total of
D) A computer system is a single 256 different characters to be represented.
physical device used for
computing and data processing.

Ans.A Ans.C

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

CA
Information Technology (MCQ for exam preparation)
47. In the binary number system, what 48. Which type of computer system is
are the possible digits? specifically designed to process vast
amounts of data and perform complex
A) 0, 1, 2, and 3 calculations at high speeds?
B) 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 A) Mainframe Computer
C) 0 and 1 B) Personal Computer (PC)
D) 0 and 9 C) Embedded Computer
D) Supercomputer
Ans.C Ans.D
49. Which of the following components 50. Which type of computing is primarily
is NOT responsible for temporarily focused on individual users and their
storing data and instructions that are personal computing needs?
currently being processed by the
CPU? A) Enterprise Computing
A) ROM (Read-Only Memory) B) End User Computing
B) GPU (Graphics Processing Unit) C) Cloud Computing
C) HDD (Hard Disk Drive) D) Mobile Computing
D) All of the above.
Ans.D Ans.B
51. Which type of memory is non- 52. Which of the following components is
volatile and typically used for responsible for converting AC (alternating
firmware in a computer system? current) from the power outlet into DC
A) Cache Memory (direct current) required by computer
B) DRAM (Dynamic Random-Access components?
Memory) A) Motherboard
C) SRAM (Static Random-Access B) Power Supply Unit (PSU)10
Memory)
C) Voltage Regulator Module (VRM)
D) ROM (Read-Only Memory) D) Uninterruptible Power Supply (UPS)
Ans.D Ans.B
53. What is the primary function of the 54. Which of the following components is
Central Processing Unit (CPU) in a considered volatile memory?
computer?
A) Hard Disk Drive (HDD)
A) To store data B) Solid State Drive (SSD)
B) To process instructions and C) Random Access Memory (RAM)
perform calculations D) Read-Only Memory (ROM)
C) To manage software updates
D) To provide a user interface
Ans.B Ans.C

10
Note: The Power Supply Unit (PSU) is responsible for converting AC (alternating current) from the power outlet into the DC (direct current) required
by the computer's internal components. The PSU provides different voltage rails to power various parts of the system, such as the CPU, motherboard,
storage devices, and peripherals.
An embedded PC is essentially any computer system that is designed for a specific use and implemented as part of a larger device, intelligent system,
or installation.

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 Information Technology
By Md. Monowar Hossain, FCA,CISA,CPFA

CA
Information Technology (MCQ for exam preparation)
55. What is the purpose of the power 56. What is the function of a heat sink in a
supply unit (PSU) in a computer? computer system?

A) To connect the computer to a A) To store data

network B) To connect peripherals
B) To supply electrical power to C) To dissipate heat from components
the internal components of the like the CPU
computer D) To increase the processing speed
C) To store data
D) To process information
Ans.B Ans.C
57. What does the acronym "BIOS" stand 58. What is the function of a network interface
for in the context of computer card (NIC) in a computer?
hardware?
A) To store data on a hard drive
A) Basic Input Output System B) To provide audio output
B) Binary Input Output System C) To enable a computer to connect to
C) Basic Interactive Operating a network
System D) To manage the display on a monitor
D) Built-In Operating System
Ans.A Ans.C
59. What is the role of the motherboard 60. Which component is used to cool the CPU
in a computer? in most desktop computers?

A) To store files and applications A) Heat sink and fan

B) To display images on the screen B) Liquid cooling system
C) To connect and allow C) External cooling pad
communication between all D) Power supply unit (PSU)
components of the computer
D) To provide internet connectivity
Ans.C Ans.A

MCQ Answer

Q 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
A A B C D A C C D D B D B B C B C A C C A

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