Chapter 1

Introduction to Information and Communication

Technology

Learning Outcome

At the end of this chapter the students should be able to:

● define and explain IT and ICT;

● explain the concepts of ICT;
● identify parts of the computer systems and their functions;
● differentiate categories of computer peripherals; and
● explain why computers are considered powerful thinking machines.

Learning Contents

● Concepts of ICT and IT

● Generations of Computers
-Types of Computers According to Size
● The Computer System and its Parts and Categories
● Uses of Computers In Modern Times
 CONCEPTS OF IT AND ICT

Information Technology (it)

⮚ It is the use of computers to store, retrieve, transmit, and manipulate data

or information. IT is typically used within the context of business operations
as opposed to personal or entertainment technologies. IT is considered to
be a subset of information and communications technology (ICT). An
information technology system (IT system) is generally an information
system, a communications system or, more specifically speaking, a
computer system – including all hardware, software and peripheral
equipment – operated by a limited group of user.

Information and Communication Technology (ICT)

⮚ It is an extensional term for information technology (IT) that stresses the role
of unified communications and the integration of telecommunications
(telephone lines and wireless signals) and computers, as well as necessary
enterprise software, middleware, storage, and audiovisual systems, that
enable users to access, store, transmit, and manipulate information

⮚ The term ICT is also used to refer to the convergence of audiovisual and
telephone networks with computer networks through a single cabling or link
system. There are large economic incentives to merge the telephone
network with the computer network system using a single unified system of
cabling, signal distribution, and management.

⮚ ICT is an umbrella term that includes any communication device,

encompassing radio, television, cell phones, computer and network
hardware, satellite systems and so on, as well as the various services and
appliance with them such as video conferencing and distance learning.

⮚ ICT is a broad subject and the concepts are evolving. It covers any product
that will store, retrieve, manipulate, transmit, or receive information
electronically in a digital form (e.g., personal computers, digital television,
email, or robots). Theoretical differences between interpersonal-
communication technologies and mass-communication technologies
have been identified by the philosopher Piyush Mathur. Skills Framework for
the Information Age is one of many models for describing and managing
competencies for ICT professionals for the 21st century.
GENERATIONS OF COMPUTERS

Generations of Computers

Fourth Fifth Generation

First Second Third
Generation (Present-
Generation Generation Generation
(1975- Beyond)
(1940-1956) (1956-1963) (1964-1975)
Present)

What is Computer generation?

Computer Generation refers to the change in technology that is used for a
computer during a time period. Initially, the generation term was used to distinguish
between varying hardware technologies. But nowadays, generation includes both
hardware and software, which together make up an entire computer system.

First Generation (1940-1956)

Hardware Software Key Characteristics Example of
Technologies Technologies Computer
● Machine ● Bulky in size ● ENIAC
language uses 0s ● Highly unreliable ● EDVAC
and 1s ● Limited commercial ● EDSAC
● Stored program use and costly ● UNIVAC 1
Figure 2.13.
concept ● Difficult commercial ● IBM 701
Vacuum tubes
Mostly scientific production
applications ● Difficult to use
● Processing speed:
milliseconds

Figure 2.14.

Electromagnetic
relay memory
 ● Punched cards
secondary
storage

Second (1956-1963)

● Assembly ● Faster, smaller, more ● Honeywell 400

Language reliable and easier to ● IBM 7030
● Batch operating program than ● IBM 1401
system previous generation ● CDC 1604
Figure 2.15.
● High-level systems ● UNIVAC LARC
Transistors
● Programming ● Commercial
languages production was still
● Scientific and difficult and costly
commercial ● Processing speed:
application microseconds

Figure 2.16.
Magnetic cores
memory
● Magnetic tapes
Disks for secondary
storage

Third (1964-1971)

● Timesharing ● Faster, smaller, more ● IBM 360/370

operating system reliable, easier and ● PDP-8
● Standardization cheaper to produce ● PDP-11
of high-level ● Commercially, easier ● CDC 6600
Figure 2.16. programming to use, and easier to
upgrade than
Integrated Circuits ● Unbundling of previous generation
(chips)
software from systems
hardware ● Scientific,
● ICs with SSI and commercial and
MSI technologies interactive on-line
● Larger magnetic applications
cores memory ● Processing speed:
● Larger capacity nanoseconds
disks and
magnetic tapes
secondary
storage
● Keyboard and
monitor
Minicomputers;
upward
compatible
family of
computers
Fourth (1971-present)

● Operating ● Small, affordable, ● IBM PC and its

systems for PCs reliable, and easy to clones
with GUI and use PCs ● Apple II
multiple windows ● More powerful and ● TRS-80
on a single reliable mainframe ● VAX 9000
Figure 2.17. terminal screen systems and
Microprocessors or
● CRAY-1
Large Scale IC
● Multiprocessing supercomputers ● CRAY-2
● Microprocessors; OS with ● Totally general
● CRAY-X/MP
semiconductor concurrent purpose machines
memory programming ● Easier to produce
● Larger capacity languages commercially
hard disks as in- ● UNIX operating ● Easier to upgrade
built secondary system with C ● Rapid software
storage programming development
● Magnetic tapes language possible
and floppy disks ● Object-oriented ● Processing speed:
as portable design and picoseconds
storage media programming
● Pointing devices ● PC, Network-
like mouse and based, and
handled devices supercomputing
applications
● Personal
computers
● Supercomputers
based on parallel
vector processing
and symmetric
multiprocessing
technologies
Spread of high-
speed computer
networks

Fifth (present- beyond)

● ULSI technology
● Development of true artificial
intelligence
● Development of Natural language
processing
● Advancement in Parallel processing
● Advancement in Superconductor
Figure 2.18. Artificial Intelligent technology
● Super Large Scale Integrated (SLSI) ● More user friendly interfaces with
chips that are able to store millions of multimedia features
components on a single chip Larger ● Availability of very powerful and
capacity main memory, hard disks with compact computers at cheaper
RAID support rates
● Optical disks as portable read-only
storage media
● Very large memory
● Notebooks, powerful desktop PCs and
workstations
● Powerful severs, supercomputers
● Internet
Cluster computing

Classification of Computers

A. According to Purpose
 1. General-purpose digital computer. This is also called all-purpose digital
computer. It can be used for any type of application.
Ex.: Computers that are used for payroll, graphics, analysis, etc.
2. Special purpose digital computer. These computers designed to solve problems
of a restricted type i.e. designed to be especially efficient in a certain class of
applications.
Ex.: Embedded systems like ATM machines.

B. According to Data Handled

1. Analog Computers. Computers that are in which numerical
magnitudes are represented by physical quantities, such as electric
current, voltage or resistance, mechanical movements, pressure or
temperature. Analog computers accept data and then process it
to produce analog data.

Figure 2.19. Example of Analog

Computer (Donner 3000)

2. Digital Computers. Work with values that are in a discrete form (or data that can
be counted). They are used for business applications, and also
scientific operations, and are ideal when 100% accuracy is
desired, thus resulting to data that are exact in values.

Figure 2.20. Digital Computer

3. Hybrid Computers. This computer is the outcome of the integration of analog

computer components and digital components. This integration is
obtained by digital –to-analog converter and analog –to-digital
converter. These computers are usually used in space vehicle
simulation and training astronauts.

Figure 2.21. Example of Hybrid Computer (DPD 45)

4. According to Capacity
Capacity refers to :
● amount of data that can be stored in memory;
● speed of internal operation of the other computer;
● capacity of storage devices; and
● number and types of peripheral devices.

a. Microcomputers
Small computers which are portable. Uses
microprocessor (the CPU on a chip), Read-Only
Memory (ROM) and a Random Access Memory (RAM).
It is sometimes known as a Single-Chip
Processor.Examples: Desktop and floor standing units,
Luggable,Laptops,Notebooks, Pocket PC’s and Pen
Figure 2.22. Desktop Computer
Computers.

b. Minicomputers
These are machines that are in the middle of
microcomputers and mainframes in terms of cost and
capability. Medium-capacity computer that is larger
than a microcomputer but smaller than most
mainframes. A minicomputer can handle a larger
amount of data than a microcomputer and can
perform most of the functions of a mainframe. These
acts as ‘servers’, which are connected to several
workstations or terminals.
Figure 2.23. Minicomputers

c. Mainframes.
The oldest category, air-cooled ,bigger in sizes,
about the size of a jeep and a powerful computer,
often serving many connected terminals and usually
used by large complex organizations like banks, airlines
 and insurance companies that handles millions of
transactions.

d. Supercomputers
The biggest and fastest computers. They can
Figure 2.24. IBM 370
perform 50 million instructions per second and are used
in applications such as nuclear weapon development
and accurate weather forecasting. These are the
fastest calculating device ever invented.

Figure 2.25. IBM DEEP

BLUE

COMPUTER SYSTEM

✔ It is a collection of entities (hardware, software and humanware) that are

designed to receive, process, manage and present information in a
meaningful format.

Software

Hardware Humanware

Computer
System
 Figure 3.1. A computer system operates on three significant components.

✔ It consists primarily of four basic units: the input unit, the storage units, the
central processing unit and the output unit. A computer performs five major
operations or functions regardless of its size and make.
These are:
● It accepts data or instructions as input;
● It stores data and instruction;
● It processes data as per the instructions;
● It controls all operations inside a computer, and ;
● Its gives results in the form of output.

Secondary
Storage

Data/ Primary Output

Input
Instructions Storage Unit
Unit
Information
Arithmetic
Logic Unit

Control Unit Indicates flow of instructions and data

Indicates the control exercised by the
control unit
Input Unit. Figure
It used3.1.for transfers’
Computer Systemraw
basic data and control
Operation signals into
the information processing system by the user before processing and computation. All
the input unit devices provide the instructions and data are transformed into binary
codes that is the primary memory acceptable format.
The functions of the input unit are:

o accept data and set of instructions/command;

o convert the data in a form which the computer can accept; and
o provide this converted data to the computer for further processing.

Central Processing Unit. This is called the brain of the computer system. It consists
of three parts namely, the control unit; the arithmetic logic unit; and the primary storage
unit.

a. Control Unit
- It controls, manages and coordinates the operations of the entire
computer system.
b. Arithmetic Logic Unit
 - It executes the instructions and performs all the calculations and
decisions.
c. Primary Storage Unit
- It is also called as main memory
- the data which is to be output from the computer system is also
temporarily stored
- it is the storage section that holds the computer programs during
execution
- it Stores temporary results of intermediate processing

Output Unit. It give the results of the process and computations to the outside
world. The output units accept the results produced by the computer, convert them
into a human readable form and supply them to the users.

COMPONENTS OF COMPUTER SYSTEM

Computer hardware – It consists of internal and peripheral devices. All physical

parts of the computer or everything that we can touch.
e.g.:Input devices, output devices, central processing unit and
storage devices

Computer software - also known as programs or applications. It gives

“intelligence” to the computer. They are classified into two classes
namely - system software and application software

Humanware – it is the person who operates computer. The user commands the
computer system to execute on instructions.

Computer Hardware Components

Hardware. It consists of all the machinery and equipment in a computer system. In

general, computer hardware is categorized according to which of the five computer
operations it performs.
▪ Input devices
▪ Processing devices
▪ Storage devices
▪ Output devices

Input Devices. It is any electronic devices connected to a computer that produce input
signals. It is also used to enter the data and instructions into the computer.
 - It translate data from form that humans understand to one that the computer
can work with.

Classification of Input Devices

a. Input Devices for Texts and Images
Keyboard Scanner Optical Mark Reader

It is the primary input device It is an electronically

that is used to enter data into extracting intended data
a computer or any other from marked fields, such
electronic device by pressing as checkboxes and fill-
keys. It uses USB or a Bluetooth Handheld Scanner infields, on printed forms.
Flatbed Scanner
device for wireless OMR technology scans a
communication to connect printed form and reads
to a computer. predefined positions and
records where marks are
Graphics Table It used to capture a source document and made on the form.
converts it into an electronic form.

It used by
artists which allow them to Barcode Reader
draw a picture onto a It is also known as
computer screen without barcode scanner or point
having to use a mouse or of sale (POS) scanner, is
keyboard. It consists of a flat, an input device capable
touch-sensitive pad and a of reading barcodes.
drawing device, either a pen
or stylus.

Digital Camera
Magnetic Ink Character Reader

It isa device used for

machine recognition of
numeric data printed with
magnetically charged ink. It
is used on bank checks and A device that takes
deposit photographs and stores
the image as data on
a memory card.

Figure 3.3. List of Input devices for Texts and Images

b. Input Devices for Audio

 Microphone
Is an input device that allows users to input audio into their computers. Here are
some uses of the microphone:

- Audio for video - Computer gaming - Online chatting

- Recording musical instruments -Recording voice for dictation, singing and podcasts

- Voice recorder - Voice recognition - VoIP – Voice over Internet Protocol

MIDI Keyboard
It is a controller keyboard, like a typically a piano-style electronic musical
keyboard, often with other buttons, wheels and sliders, used for sending MIDI
signals or commands over a USB or MIDI 5-pin cable to other musical devices or
computers.

Figure 3.4. List of Input devices for Audio

c. Input Devices for Video

CCTV Camera Digital Video Camera

Webcam

Video input are motion images captured into

the computer by special input devices.

Figure 3.4. List of Input devices for Video

d. Pointing Device

Pointing Device is an input device that allows a user to control a pointer on a screen. A
pointer is a small symbol on the screen whose location and shape change as a user
moves a pointing device
 Mouse Trackball Touchpad Joystick

Figure 3.5. List of Pointing Input devices

Output Devices. Hardware that is capable of delivering or showing information to one

or more users. An output device displays, prints and presents the results of a computers
work.
After processing the inputted data, the computer will give its output. This output
can be in two different formats:
1. Softcopy – Visual (monitor) or Sound (speakers)
2. Hardcopy – Output on a tangible (something you can touch) such as a
printer printout

Different Types of Output Devices

LCD Monitor LED Monitor LCD Projector

LCD Monitor

Dot Matrix Printer Laser Printer Ink Jet Printer Thermal Printer

Speaker Earphone
Woofer Headset

Figure 3.7. Different Types of Output Devices

Storage Devices. It is any hardware device that is used for storing, porting and extracting
data files and objects. It can hold and store information either temporarily and
permanently, and can be internal or external to a computer.

Types of Computer Storage

 1. Primary storage
2. Secondary storage

1. Primary Storage. Primary storage is the main memory in a computer. It stores data
and programs that can be accessed directly by the processor.
There are two types of primary storage which are RAM and ROM

Figure 3.8. RAM and ROM

Table 3.1. The Difference between RAM and ROM
Random-Access Memory (RAM) Read-Only Memory (ROM)
RAM is an acronym for Random- Access ROM is an acronym for Read- Only
Memory which means the data and Memory. The data or program in ROM can
program in RAM can be read and only be read but cannot be written at all
written.
RAM stores data during and after ROM is another type of memory
processing. RAM is also known as a permanently stored inside the computer.
working memory.
The data in RAM can be read (retrieved) All the contents in ROM can be accessed
or written (stored). and read but cannot be changed.
RAM is volatile which means the ROM is non-volatile. It holds the programs
programs and data in RAM are lost and data when the computer is powered
when the computer is powered off. off.
A computer uses RAM to hold Programs in ROM have been
temporary instructions and data prerecorded.
needed to complete tasks. This enables It can only be stored by the manufacturer
the CPU (Central Processing Unit) to once and it cannot be changed.
access instructions and data stored in
the memory very quickly

2. Secondary Storage - Secondary storage is another alternative storage to save

your work and documents. This can be removable, internal, or external. It is very
useful to store programs and data for future use. It is non-volatile, which means
that it does not need power to maintain the information stored in it. It will store the
information until it is erased.
 Secondary
Storage

Magnetic Optical Flash

Medium Medium Memory

Figure 3.9. Types of Secondary Story

Types of Secondary Storage

a. Magnetic Medium. It is a non-volatile storage medium. It can be any type of

storage medium that utilizes magnetic patterns to represent information.
Examples of magnetic storage are magnetic disk such as a floppy disk, used for
off-line storage; hard disk, used for secondary storage and magnetic tape such as
video cassette; audio storage reel-to-reel tape.

Floppy Disk Magnetic Tape

Hard Disk Video Cassette
Figure 3.10. Types of Magnetic Medium

b. Optical Medium. It is a non-volatile storage media, holds content in digital form

that are written and read by laser. These media include various types of CDs and
DVDs.
Types of Optical Medium

CD CD ROM DVD CD-R CD-RW DVD-RW DVD-RAM

Figure 3.11. Types of Optical Medium

c. Flash Memory. It is a solid-state, non-volatile, rewritable memory that functions like

RAM and a hard disk drive. Flash memory store bits of electronic data in memory
cells just like DRAM (Dynamic RAM) but it also works like a hard disk drive that when
the power is turned off, the data remains in the memory. Flash memory cards and
flash memory sticks are examples of flash memory.
 Types of Flash Memory

Solid State Hard Memory Stick Flash memory Micro Flash Memory
Disc
Figure 3. 12. Types of Flash Memory

CAPACITY. It refers to the number of bytes (characters) a storage medium can hold
1 Byte = 8 Bits 1 KB = 1024 Byte
1 Megabyte = 1024 Kilobyte 1GB = 1024 MB
1 Terabyte (TB) = 1 trillion byte 1 Petabyte (PB) = 1 quadrillion byte
1 Exabyte (EB) = 1 quintillion byte 1 Zetabyte (ZB) = 1 sextillion byte
1 Yotabyte (YB) = 1 septillion byte
Table 3.2. Different Storage Capacity

System Unit
The system unit is a boxlike case that houses the computer’s main hardware
components
Parts of a System Unit
1. Motherboard/Mainboard. The motherboard is the
main circuit board holding the integrated circuits for the
microprocessor, memory, etc. The motherboard also supports
internal connectors for the hard disk drives & optical drives
(CD, DVD), etc, and external connectors for the mouse,
keyboard, printer, speakers, etc.

Figure 3.13. Motherboard

2. Hard Disk Drive Storage (HDD). It used as the main

storage device for programs and data when the computer is not
being used. Information is stored on the hard drive magnetically
and the capacity of the device is usually measured in Megabytes,
Gigabytes, or Terabytes, etc.
Figure 3.14. Hard Disk Drive
 3. Optical Drive (CD/DVD). A DVD drive allows removable
optical discs to be used to store information.

Figure 3.15. Optical Drive

4. Memory/RAM. Memory is the processor’s working area and is here all operations
actually take place while the computer is running.
Memory is also called Random Access Memory and consists
of small memory ‘chips’ which fit into slots on the motherboard.
Figure 3.16. Memory

5. Microprocessor/Central Processing Unit/CPU. This is the

‘computer on a chip’ and is the device which actually
executes the instructions.

Figure 3.17. Microprocessor/CPU

Components of the CPU

a. Control unit. Coordinates and controls all parts of the computer
system.
b. Arithmetic-logic unit. Performs arithmetic or
logical operations
c. Registers. Temporarily store the most frequently used instructions
Figure 3.18. Processor
and data

6. Computer Power Supply. This supplies the electricity to all the

parts in the computer.

Figure 3.19. Computer Power Supply

7. Heat Sink/Fan. This sits on top of the CPU and draws heat up
into the fins of the Heat Sink, and then the Fan pulls air up and
through the fins cooling them. That is how the CPU is stays cool,
otherwise it would over heat and shut down the computer.
Figure 3.20. Heat Sink/Fan
8. Network card. Attach to the PCI (Peripheral component interconnect ) slot used
for a Broadband connection, like cable or DSL.

Figure 3.21. Network Card

9. Sound Card. It is a computer expansion card that facilitates

the input and output of audio signals to and from a computer
under control of computer programs.
Figure 3.22. Sound Card

10. Graphics Card. It is an expansion card whose function is to

generate and output images to a display

Figure 3.23. Graphics Card

11. Chipset. It is a collection of chips that provide the switching

circuitry needed to move data throughout the computer.

Figure 3.24. Chipset

12. Cooling Fan. Cooling Fan is used for cooling purposes.

Figure 3.25. Cooling Fan

13. CMOS Battery. It provides CMOS with the power when the
computer is turned off all motherboards comes with a battery.
These batteries mount on the motherboard in one of three ways:
the obsolete external battery, the most common onboard
battery, and built-in battery.
Figure 3.26. CMOS Battery
CMOS – Complementary Metal Oxide Semi- Conductor

14. IDE (Integrated Drive Electronics) Controller. It is

responsible for controlling the hard drive and CDROM.

Figure 3.27. IDE (Integrated Drive Electronics) Controller

 15. SATA (Serial Advance Technology Attachment)
Controller. Major upgrade of IDE controller, responsible for
controlling the hard drive and CDROM.
Figure 3.28. SATA (Serial Advance Technology Attachment)
Controller

Computer Software Components

Computer Software
It refers to the set of computer programs, procedures that describe the programs,
how they are to be used. We can say that it is the collection of programs, which increase
the capabilities of the hardware. Software guides the computer at every step where to
start and stop during a particular job. The process of software development is called
programming.
Computer software is a generic term for organized collections of code
representing instructions executed by a computer. Software is often written first as source
code, and then converted to a binary format that is specific to the device on which the
code will be executed.

Categories of Software
Computer software is normally classified into two broad categories.
● System Software
● Application Software

SYSTEM SOFTWARE
⮚ It is responsible for controlling, integrating, and managing the individual
hardware components of a computer system so that the other software
and the users of the system see it as a functional unit without having to be
concerned with the low-level details such as transferring data from memory
to disk, or rendering text onto a display.
⮚ These are general programs designed for performing tasks such as
controlling all operations required to move data into and out of the
computer.
 ⮚ It communicates with printers, card reader, disk, tapes etc. monitor the use
of various hardware like memory, CPU etc.
So without system software it is impossible to operate your computer. The following
diagram is shown in Figure 3.29 is the relation between hardware, software and you as a
user of computer system.

USERS

APPLICATION
SOFTWARE

SYSTEM
SOFTWARE

HARDWARE

Figure 3. 29. Relation between hardware, software and user

Types of System Software

1. Operating System

⮚ It is software that controls and monitors the running of applications

⮚ It provides a “platform” for software developers who have to design
applications with the OS in mind.
⮚ It is responsible for the management and coordination of activities
and the sharing of the resources of the computer
⮚ It is an interface between computer and user.

Figure 3.30. Operating System is an interface between computer

Function of an Operating System

The part of the OS that manages the computer’s resources is known as the
Kernel (otherwise known as the supervisor program). It manages the computer’s
resources (CPU, memory and peripherals).

Memory Resource Backing Store Secondary-

Management Allocation and Management Storage
Sharing Management

Process Communication File I/O System

Management Management Management Management

Interrupt Networking Job Device Security

Handling Accounting Management

Figure 3.31. Function of an Operating System@ guru99.com

Most operating systems perform the following tasks:

a. Memory Management. In several programs can be opened at once,
the OS has to allocate memory to each program that is running,
including itself.
b. Resource Allocation and Sharing. Some computer systems can “multi-
task”, i.e. several programs can run at once. The OS allocates
processing time, memory and resources to each.
c. Backing Store Management. The OS maintains a directory of the HDD so
that files and free space can be located quickly. The OS controls the
transfer of the data from disk to memory and back again.
 d. Interrupt Handling. The OS will detect “interrupts”, e.g. when the printer
is out of paper; when the user is pressing the ESC key; or when a
hardware device or an application is malfunctioning. The OS will display
the appropriate error message and may suggest corrective action to
the user.
e. Process management. It helps OS to create and delete processes. It also
provides mechanisms for synchronization and communication among
processes.
f. File management. It manages all the file-related activities such as
organization storage, retrieval, naming, sharing, and protection of files.
g. Device Management. It keeps tracks of all devices. This module also
responsible for this task is known as the I/O controller. It also performs the
task of allocation and de-allocation of the devices.
h. I/O System Management. One of the main objects of any OS is to hide
the peculiarities of that hardware devices from the user.
i. Secondary-Storage Management. Systems have several levels of
storage which includes primary storage, secondary storage, and cache
storage. Instructions and data must be stored in primary storage or
cache so that a running program can reference it.
j. Security. This module protects the data and information of a computer
system against malware threat and authorized access.
k. Command interpretation. This module is interpreting commands given
by the acting system resources to process that commands.
l. Networking. A distributed system is a group of processors which do not
share memory, hardware devices, or a clock. The processors
communicate with one another through the network.
m. Job accounting. It keeps track of time & resource used by various job
and users.
n. Communication management. The Coordination and assignment of
compilers, interpreters, and another software resource of the various
users of the computer systems.

Types of Operating System

 Batch Multitasking/Time
Operating Sharing OP
System

Mobile Multi-
Real Time
OS processing
OP
OS

Distributed Network
OS OS

Network
OS

Figure 3.32. Types of Operating System

1. Batch Operating System

BATCH
U
U JOBS C
JOB
S
S OPERATING P
E JOB SYSTEM
E U
R
R JOBS
JOB BATCH

Figure 3.33. Batch Operating System

● Some computer processes are very lengthy and time-consuming. To

speed the same process, a job with a similar type of needs are
batched together and run as a group.
● The user of a batch operating system never directly interacts with the
computer. In this type of OS, every user prepares his or her job on an
offline device like a punch card and submit it to the computer
operator.
2. Multi-Tasking/Time-sharing Operating Systems

Word

Web OPERATING C
Browser SYSTEM P
U

Printing

Figure 3.34. Multi-Tasking/Time-Sharing Operating System

● Time-sharing operating system enables people located at a different

terminal (shell) to use a single computer system at the same time.
● The processor time (CPU) which is shared among multiple users is
termed as time sharing.

3. Real time
User

Application Program

Real Time Operating System

Hardware

Figure 3.35. Real Time Operating System

● It is also known as embedded operating system and it is totally

depending upon the clock interrupts.
 ● A real time operating system time interval to process and respond to
inputs is very small. Examples: Military Software Systems, Space Software
Systems.

4. Distributed Operating System

Workstation Terminal File Server

Communication
Network

Database Server Computer Node Workstation

Figure 3.36. Distributed Operating System

● It is used in many processors located in different machines to provide

very fast computation to its users.
● It is a model where distributed applications are running on multiple
computers linked by communication network.
● It is also an extension of the network operating system that supports
higher levels of communication and integration of the machines on the
network.

5. Network Operating System

Network Operating System runs on a server. It provides the capability to serve to

manage data, user, groups, security, application, and other networking functions.
File Server

Clients

Clients
 Figure 3.37. Network Operating System

6. Mobile OS

Figure 3.38. Mobile Operating System

● Is are those OS which is especially that are designed to allows and power
smartphones, tablets, and wearables devices to run applications and
programs.
● Some most famous mobile operating systems are Android and iOS, but
others include BlackBerry, Web, and watchOS.

Examples of Operating System

a. The Unix Operating System. It was first created in Bell Labs way back
in the 1960s. It became popular in the 1970s for high-level
computing, but not on the consumer level. Since a lot of Internet
services were originally hosted on Unix machines, the platform
gained tremendous popularity in the 1990s. It still leads the industry
as the most common operating system for Web servers.
b. The Macintosh OS (Mac OS). Develop by Apple Computer in
January 24, 1984. It is pre-installed on the Macintosh 128K model
computer. The Mac OS is credited for the widely used feature of
every OS to date. The GUI (Graphical User Interface); the use of
icons, buttons a pointing cursor, and a point and click command to
 execute instructions rather than the usual command line driven
interface.
c. The MS-DOS (Microsoft-Disk Operating System). It commercialized
by Microsoft. It was the most dominant operating system for the PC
compatible platform during the 1980’s. It is command line driven
interface program where the user interacts with the computer
through command prompts to execute different program.
d. Microsoft Windows Operating System. It is first introduced an
operating environment named Windows in November 1985 as an
add-on to MS-DOS in response to the growing interest in graphical
user interface (GUI).
e. Linux Operating System. Linux is an open source operating
system (OS) for personal computers, servers and many other
hardware platforms that is based on the Unix operating system. Linux
was originally created by Linus Torvalds as a free alternative
operating system to more expensive Unix systems. Linux has grown
since its creation due in part to its open source roots. Open source
software is freely licensed and users may copy and even change
the code.
There are several operating systems that use the Linux
kernel. These include: Ubuntu, Debian, Red Hat, Fedora, Chrome OS
and Android (for smartphones).

2. Utilities Programs
⮚ This are small, powerful programs with a limited capability, they are
usually operated by the user to maintain a smooth running of the
computer system. Various examples include file management,
diagnosing problems and finding out information about the
computer etc. Notable examples of utility programs include copy,
paste, delete, and file searching, disk defragmenter, disk cleanup.

3. Device Drivers
⮚ Specialized programs that allow communication between a device
and the computer. Loaded into memory each time a computer is
started. When a new device is added, new device drivers must be
installed.
APPLICATION SOFTWARE
It is a type of software that performs task to directly benefit
or assist the user. It is installed on top of an Operating System such
as MS Windows.

Types of application software

a. Proprietary Application Software / Customized Software. It is software
designed for a particular customer. In this case we need to hire a computer
programmer or software creator to develop software for the customer.
b. Packaged software. It is the kind of “off-the-shelf application software”
program developed for sale to the general public. It can be purchased
programs, leased, or rented from a vendor that develops programs and
sells them to many organization. The word package is a commonly used
term for a computer program (or group of programs) that has been
developed by a vendor and is available for purchase in a prepackaged
form.

Examples of Application Software

1. Word Processing software - Use this kind of tool to create worksheets,
type letters, and type papers. The following examples are MS Word,
WordPerfect, MS Works, and AppleWorks.
2. Desktop Publishing software - Use this software to make signs, banners,
greeting cards, illustrative worksheets, newsletters, etc. The following
examples are Adobe PageMaker, MS Word, MS Publisher, AppleWorks,
MS Works, and Quark Express.
3. Spreadsheet software - Use this kind of tool to compute number-
intensive problems such as budgeting, forecasting, etc. A spreadsheet
will plot nice graphs very easily. The following examples are MS Excel,
Quattro Pro, Lotus 1-2-3, MS Works, and AppleWorks.
4. Database software - Use this software to store data such as address,
membership and other text information. A database can be used to
easily sort and organize records. The following examples are MS Access,
Filemaker Pro, AppleWorks, and MS Works.
5. Presentation software - Use this software to create multimedia stacks of
cards/screens that can effectively present a lesson or a sales pitch. The
user often clicks on buttons to advance to the next screen in a
 sequence. The following examples are MS PowerPoint, AppleWorks
(slideshows), HyperStudio, Flash, Director, HyperCard, Digital Chisel,
SuperCard, and Corel Envoy.
6. Internet Browsers - This software allows one to surf the Web. Often they
can read email and create Web pages too. The following examples are
Netscape Navigator (or Netscape Communicator), MS Internet Explorer,
AOL Browser, Google Chrome, Mozilla Firefox, Opera Web Browser, and
Safari Web Browser.
7. Email programs - These programs send and receive email. The following
examples are Netscape Messenger (part of Netscape Communicator),
MS Outlook Express, MS Outlook, Eudora, and AOL browser.
8. Graphics Programs (pixel-based) - This software allows one to touch up
photographs and create graphics from scratch. The following examples
are Adobe Photoshop, Paint Shop Pro, AppleWorks, MS Works, MS Paint
(comes free on Windows PC's), and Painter.
9. Graphics Programs (vector-based) - This software creates graphics that
are similar to illustrations or cartoon drawings. The following examples
are Adobe Illustrator, Corel Draw, AppleWorks, MS Works, and MS Word.
10. Communications software - This software allows two computers with
modems to communicate through audio, video, and/or chat-based
means. The following examples are MS NetMeeting, AOL Instant
Messenger, IRC, ICQ, and CU-SeeMe.

Capabilities of Software
a. Object Linking and Embedding (OLE). It allows information to be shared
between applications, e.g. a spreadsheet created in Excel can be
imported into Word.
b. Portability of Data. People, who have different types of computers with
different operating systems and applications, often need to transfer files
and programs among their computers. FTP (File Transfer Protocol) allows
files to be transferred over the Internet among different types of computers.
c. Upgradability. Software upgrades can provide new and useful features but
they can also cause problems, such as documents may not be compatible
versions, e.g. a Word 6 file can be read in Word 97 but a Word 97 file cannot
be read in Word 6; data formatting may be lost if a Word 97 document is
saved to Word 6 format because Word 97 contains new features that Word
6 does not have; upgraded software frequently required more memory,
more disk space and a faster processor, so hardware need to be
upgraded.
 Humanware

It describes the customer experience of software and hardware. More

particularly, it has to do with the facilities of a computer system being developed
based on the interests and needs of a user.

It is also called as the living ware. It refers to the users of the computer
system, either direct or indirect users.

System Computer
Analyst Operator
Computer
Engineers Software
Engineers
Project
Manager
Technicians
Database
Administrator Peopleware
Web Developer

Programmer Server
Administrator
Individual people who
uses computer in their Information
job, entertainment etc. Technology
Specialist

Figure 3.39. Different types of humanware

Computer Engineers.
o they are engage in software design and application to address the
needs of a particular industry or sector. They are primarily responsible
for the update in the software as well as providing additional
customization of current software to ensure the system’s functionality.
Software Engineers
o they are primarily responsible for the design and development of the
software of the computers, as well as its testing and evaluation.
Information Technology Specialists
o they tasked to plan and coordinate the installation, operation,
troubleshooting and maintenance of the computer’s software and
hardware systems.
Website Designer
 o they are engage in the construction of the navigation schemes of a
website.
Compute Technicians
o They in charge with the repair and maintenance of computers and
its servers
o They also build or configure new hardware as well as installing and
bringing up to date the software
o They are also tasked with the creation and maintenance of
computer networks.

Computer Operator
o They are responsible for monitoring and controlling computer systems
especially mainframe computer systems in a company or
organization.
System Analyst
o They work to solve problems related to computer technology. Many
analysts set up new computer systems, both the hardware and
software; add new software applications to increase computer
productivity.
Project Manager
o They are the person who has the overall responsibility for the
successful initiation, planning, design, execution, monitoring,
controlling and closure of a project.
Programmer
o They refer to a specialist in one area of computer programming or to
a generalist who writes code for many kinds of software.
Database Administrator
o They are responsible for the performance monitoring, security,
integrity, troubleshooting, as well as backup and data recovery of a
database. They use specialized software to store and organize data.
Server Administrator
o It has the overall of a server. This is usually in the context of a business
organization, where a server administrator overseas the performance
and condition of multiple servers in the business, or it can be in the
context of a single person running a game server.
USES OF COMPUTERS IN MODERN TIMES

1. Information Systems/Data Processing

Information System or Data Processing refers to a category of computer use that enables
organization to utilize to the fullest the data they possess.

2. Personal Computing
Small and medium-size businesses as well as individuals form the bulk of personal
computing practitioners. Personal computing means the use of stand-alone computers
equipped with all the system, utility, and application software and I/O devices that an
individual needs to perform one or more tasks.

3. Science and Research

Result of scientific endeavors would take a long time to realize if it were not for the use of
computers in this specialty area.

4. Education
Although computers will never replace books and teachers, the can enhance learning
in a way no other medium can. Through its interactive capability, computers have added
a new dimension to the learning process.

5. Artificial Intelligence
Artificial intelligence is an area of computer research which aims to endow the computer
with certain forms of human intelligence such as the capability to understand natural
language or to reasons under uncertain condition.

Field of Artificial Intelligence is divided into four categories:

1. Knowledge-based and expert system refers to man’s knowledge based on his

judgment algorithmic sense about a specific application area.
2. Natural languages refer to software that enables computer systems to accept,
interpret and execute instructions written in the native or natural language or the
end user.
 3. Simulation of human sensory capabilities in computer system, such as seeing,
hearing and touching, has been made possible, although in varying report,” the
computer will obligingly follow.
4. Robotics refers to the use of computerized robots in the manufacturing sector.
Industrial robots, which are usually equipped with an arm and a hand, can be
instructed to do repetitive tasks such as screwing on the bolts or painting cars.

The Computer System and its Parts and Categories

 What is a Computer System?
A computer is a machine that can be instructed to carry out sequences of
arithmetic or logical operations automatically via computer programming. Modern
computers have the ability to follow generalized sets of operations, called programs.
These programs enable computers to perform an extremely wide range of tasks. A
"complete" computer including the hardware, the operating system (main software), and
peripheral equipment required and used for "full" operation can be referred to as a
computer system. This term may as well be used for a group of computers that are
connected and work together, in particular a computer network or computer cluster.

Computers are used as control systems for a wide variety of industrial and
consumer devices. This includes simple special purpose devices like microwave ovens
and remote controls, factory devices such as industrial robots and computer-aided
design, and also general purpose devices like personal computers and mobile devices
such as smartphones. The Internet is run on computers and it connects hundreds of
millions of other computers and their users.

Early computers were only conceived as calculating devices. Since ancient times,
simple manual devices like the abacus aided people in doing calculations. Early in the
Industrial Revolution, some mechanical devices were built to automate long tedious
tasks, such as guiding patterns for looms. More sophisticated electrical machines did
specialized analog calculations in the early 20th century. The first digital electronic
calculating machines were developed during World War II. The first semiconductor
transistors in the late 1940s were followed by the silicon-based MOSFET (MOS transistor)
and monolithic integrated circuit (IC) chip technologies in the late 1950s, leading to the
microprocessor and the microcomputer revolution in the 1970s. The speed, power and
versatility of computers have been increasing dramatically ever since then, with MOS
transistor counts increasing at a rapid pace (as predicted by Moore's law), leading to the
Digital Revolution during the late 20th to early 21st centuries.

Conventionally, a modern computer consists of at least one processing element,

typically a central processing unit (CPU) in the form of a metal-oxide-semiconductor
(MOS) microprocessor, along with some type of computer memory, typically MOS
semiconductor memory chips. The processing element carries out arithmetic and logical
operations, and a sequencing and control unit can change the order of operations in
response to stored information. Peripheral devices include input devices (keyboards,
mice, joystick, etc.), output devices (monitor screens, printers, etc.), and input/output
devices that perform both functions (e.g., the 2000s-era touchscreen). Peripheral devices
allow information to be retrieved from an external source and they enable the result of
operations to be saved and retrieved.

Input Devices
An input device is essentially a piece of hardware that sends data to a computer.
Most input devices either interact with or control the computer in some way. The most
common input devices are the mouse and the keyboard, but there are many others. The
key distinction between an input device and an output device is that the former sends
data to the computer, whereas the latter receives data from the computer. Input and
output devices that provide computers with additional functionality are also called
peripheral or auxiliary devices.

1. Keyboard
Keyboards are the most common type of input device. Before keyboards, interaction
with computers was generally carried out using punch cards and paper tape. Most
English language keyboards use the QWERTY layout for the alphabetic keys, which are
surrounded by number, symbol, function, and other key types. By pressing the relevant
keys, a user can feed data and instructions to the computer.
2. Mouse
A mouse interacts with a computer through a process known as "point and click."
Essentially, when a user moves the mouse on the mouse pad, the pointer moves in a
corresponding direction on the computer's monitor screen. The concept of a computer
mouse has its roots in the trackball, a related pointing device invented in 1946 that used
a "roller ball" to control a pointer. Most modern computer mice have two buttons for
clicking and a wheel in the middle for scrolling up and down documents and web pages.
3. Touchpad
Also known as a trackpad, a touchpad is a common substitute for a computer mouse. It
is essentially a specialized surface that can detect the movement of a user's finger and
use that information to direct a pointer and control a computer. Touchpads were first
introduced for laptops in the 1990s, and it's now rare to find a laptop without one.

4. Scanner
The word "scanner" can be used in a number of different ways in the computer world,
but here I am using it to refer to a desktop image scanner. Essentially, a scanner is an
input device that uses optical technology to transfer images (or sometimes text) into a
computer, where the signal is converted into a digital image. The digital image can then
be viewed on a monitor screen, saved, edited, emailed, or printed.

5. Digital Camera
Digital cameras are used to capture photographs and videos independently. Later,
these photo and video files can be transferred to a computer by connecting the camera
directly with a cable, removing the memory card and slotting it into the computer, or
through wireless data transfer methods such as Bluetooth. Once the photos are on the
computer, they can be saved, edited, emailed, or printed.

6. Microphone
A microphone captures audio and sends it to a computer where it is converted to a
digital format. Once the audio has been digitized, it can be played back, copied, edited,
uploaded, or emailed. Microphones can also be used to record audio or to relay sounds
live as part of a video chat or audio stream.

7. Joystick
Joysticks are commonly used to control characters and vehicles in computer video
games. Essentially, a joystick is a handle that pivots on a base and sends its angle or
direction to the computer as data. Many video gaming joysticks feature triggers and
buttons that can be pressed to use weapons or projectiles in games.

8. Graphic Tablet
Also known as digitizers, graphic tablets are input devices used for converting hand-
drawn artwork into digital images. The user draws with a stylus on a special flat surface as
if they were drawing on a piece of paper. The drawing appears on the computer screen
and can be saved, edited, or printed. While scanners can only create digital images from
drawings, graphic tablets offer greater control and versatility for artists by allowing them
to see their drawing appear live on their monitor as they create it.

9. Touch Screen
Many devices nowadays use a touch screen rather than a mouse as a way for users to
point, drag, or select options on a screen. As the name suggests, a touch screen is a
touch-sensitive monitor screen that reacts to fingers moving across it. Touch screens are
particularly common in portable devices, such as tablets, palmtops, laptops, and
smartphones.

10. Webcam
Webcams are different from digital cameras in two ways. Firstly, they cannot operate
independently from a computer, and second, they have no inbuilt memory. Although
webcams can capture photographs and videos, they are more often used to live-stream
videos or facilitate video chats.

Output Devices

What Is an Output Device?

An output device is a piece of computer hardware that receives data from a computer
and then translates that data into another form. That form may be audio, visual, textual,
or hard copy such as a printed document.

The key distinction between an input device and an output device is that an input device
sends data to the computer, whereas an output device receives data from the
computer.

For example, using a microphone to record a podcast is an example of using an input

device. Listening to the recorded podcast through a connected speaker is an example
of using an output device. Both output and input devices are examples of auxiliary or
peripheral devices.

Analyzing the Functionality of a Device

There are four different categories of output device: visual, data, print, and sound. Each
output device example has a specific history, so here I cover specifically how each
device works, when it became a part of technology history, popular brands on the market
selling the device, and a fun fact.

1. Monitor
Mode: Visual
Function: A monitor consists of a screen, circuitry, a power supply, buttons to adjust
screen settings, and a casing that contains all of these components. A monitor displays
data from a computer onto a screen so the user can interact with the data via a digital
interface.

Popular Brands: Acer, Alienware, Apple, Asus, Dell, HP, LG, Lenovo, Samsung

Origin Story: The first monitors used the same technology as early televisions, relying
on a cathode ray tube and a fluorescent screen. This technology was first utilized for
computer monitors in 1965 in the Uniscope 300 machine, which had a built-in CRT display.
CRT display lights up a series of dots with a beam on an active part of the screen. This
resulted in a maximum resolution of 1600 by 1200 pixels. LCD (liquid crystal display)
entered the market in 2000 and outsold CRT monitors in 2007. Nowadays, monitors
incorporate flat display technology. Plasma monitors are brighter than both CRT and LCD
and function by illuminating tiny charged gas bubbles, or plasma, in the screen.

2. Printer
Mode: Print
Function: The function of a printer is to create a copy of whatever is sent from the
computer to the printer. Printers take electronic data sent from a computer and generate
a hard copy.

Popular Brands: Brother, Canon, Epson

3. Headphones
Mode: Sound

Function: Headphones output audio from a computer through two individual

headphones for a single listener. Also known as earphones, headphones allow you to
listen to audio without disrupting other people in the vicinity.

Popular Brands: Sennheiser, JBL, Bose, Sony, Skullcandy

4. Computer Speakers
Mode: Sound

Function: Computer speakers are hardware devices that transform the signal from the
computer's sound card into audio. Speakers create sound using internal amplifiers that
vibrate at different frequencies according to data from the computer. This produces
sound.

5. Projector
Mode: Visual

Function: As its name suggests, this output device "projects" computer images or video
onto a wall or screen.
6. GPS (Global Positioning System)
Mode: Data

Function: GPS is a radio-based navigation system that’s composed of a sender computer

and a receiver. The sender broadcasts signals to 24 satellites that ping to the sender the
exact location of the sender computer in the form of latitude and longitude coordinates.
The satellites use microwave signals to “talk” to the GPS, giving information on location,
vehicle speed, and a number of other pieces of data.

7. Sound Card
Mode: Sound

Function: The sound card controls the output of sound signals, enabling devices like
speakers and headphones to work. The sound card is known as an expansion card, which
means it can be added to the motherboard. Although a sound card is not essential to a
computer's basic functionality, you need one if you wish to play games, watch movies,
listen to music, and use audio and video conferencing.

Popular Brands: Audigy, ASUS, Creative, EVGA

8. Video Card
Mode: Visual

Function: As with the sound card, the video card is an expansion card that slots into the
motherboard. The video card processes images and video, enabling visuals to be seen
on a display. Most computers have basic video and graphics capabilities built into the
computer's motherboard, but for faster, more detailed graphics, a video card is required.

Popular Brands: NIVIDIA, ASUS, MSI, EVGA

9. Braille Reader
Mode: Print

Function: A braille reader is a peripheral device that enables a blind person to read text
displayed on a computer monitor. The text is sent by the computer to the device, where
it is translated into a braille format and made readable by pushing rounded pins up
through a flat surface. Braille readers are also called braille displays and come in various
sizes. Braille readers come in the form of separate devices from a keyboard or as part of
a keyboard. Most use piezoelectric technology, or electricity generated by mechanical
stress, to create a single line of text at a time in the form of raised bumps.

10. Speech-Generating Device (SGD)

Mode: Sound

Function: SGDs, also known as voice output communication aids, generate text to
speech. A user types something and when the command is sent, the SGD reads the
sentence out loud.

What is Digital Data Storage?

Digital data storage is essentially the recording of digital information in a storage
medium, typically by electronic means. The storage device usually enables a user to store
large amounts of data in a relatively small physical space, and makes sharing that
information with others easy. The device may be capable of holding the data either
temporarily or permanently.

Digital data storage devices have many uses. For example, computers usually depend
upon information storage to function. Storage media can also be used to back up
important information (storing digital data can involve durability and reliability issues, so
making independent copies of the information is normally a wise precaution). Some
storage devices are also portable, meaning that they can be used to transfer information
from one computer to another.

Digital data storage media generally fall into one of five categories: magnetic storage
devices, optical storage devices, flash memory devices, online/cloud storage, and
paper storage. I will give one or more examples of each category below.

1. Hard Disk Drive

A hard disk drive (also known as a hard drive, HD, or HDD) can be found installed in almost
every desktop computer and laptop. It stores files for the operating system and software
programs, as well as user documents, such as photographs, text files, and audio. The hard
drive uses magnetic storage to record and retrieve digital information to and from one
or more fast-spinning disks.

2. Floppy Disk
Also know as a diskette, floppy, or FD, the floppy disk is another type of storage medium
that uses magnetic storage technology to store information. Floppy disks were once a
common storage device for computers and lasted from the mid-1970's through to the
start of the 21st century. The earliest floppies were 8-inch (203 mm) in size, but these were
replaced by 5 1⁄4-inch (133 mm) disk drives, and finally a 3 1⁄2 inch (90 mm) version.

3. Tape
In the past, magnetic tape was often used for digital data storage, because of its low
cost and ability to store large amounts of data. The technology essentially consisted of a
magnetically thin coated piece of plastic wrapped around wheels. Its relative slowness
and unreliability compared to other data storage solutions has resulted in it now being
largely abandoned as a media.

4. Compact Disc (CD)

The compact disc, known for short as a CD, is a form of optical storage, a technology
which employs lasers and lights to read and write data. Initially compact discs were used
purely for music audio, but in the late 1980's they began to be also used for computer
data storage. Initially, the compact discs that were introduced were CD-ROM's (read
only), but this was followed by CD-R's (writable compact discs) and CD-RW's (re-writable
compact discs).

5. DVD and Blu-ray Discs

The DVD (digital versatile disc) and Blu-ray disc (BD) are formats of digital optical disc
data storage which have superseded compact discs, mainly because of their much
greater storage capacity. A Blu-ray disc, for example, can store 25 GB (gigabytes) of
data on a single-layer disc and 50 GB on a dual-layer disc. In comparison, a standard CD
is the same physical size, but only holds 700 MB (megabytes) of digital data.

6. USB Flash Drive

Also known as a thumb drive, pen drive, flash-drive, memory stick, jump drive, and USB
stick, the USB flash drive is a flash memory data storage device that incorporates an
integrated USB interface. Flash memory is generally more efficient and reliable than
optical media, being smaller, faster, and possessing much greater storage capacity, as
well as being more durable due to a lack of moving parts.

7. Secure Digital Card (SD Card)

A common type of memory card, SD cards are used in multiple electronic devices,
including digital cameras and mobile phones. Although there are different sizes, classes,
and capacities available, they all use a rectangular design with one side "chipped off"
to prevent the card from being inserted into the camera or other device the wrong way.

8. Solid State Drive (SSD)

A solid state drive uses flash memory to store data and is sometimes used in devices such
as netbooks, laptop, and desktop computers instead of a traditional hard disk drive. The
advantages of an SSD over a HDD include a faster read/write speed, noiseless operation,
greater reliability, and lower power consumption. The biggest downside is cost, with an
SSD offering lower capacity than an equivalently priced HDD.

9. Cloud Storage
With users increasingly operating multiple devices in multiple places, many are turning to
online and cloud computing solutions. Cloud computing basically involves accessing
services over a network via a collection of remote servers. Although the idea of a "cloud
of computers" may sound abstract to those unfamiliar with this metaphorical concept, in
practice it can provide tremendous storage solutions for devices that are connected to
the internet.

10. Punch Card

Punch cards (or punched cards) were a common method of data storage used in the
early computers. Basically, they consisted of a paper card with punched or perforated
holes that have been created by hand or machine. The cards were entered into the
computer to enable the storage and accessing of information. This form of data storage
media pretty much disappeared as new and better technologies were developed.

GENERATIONS OF COMPUTERS

FIRST GENERATION OF COMPUTERS

• Characterized by vacuum tubes started in 1951.
• UNIVAC I (Universal Integrated Automatic Computer)
• UNIVAC first commercially viable electronic digital computer
• It handled alphabetic characters instead of just numbers.
• IBM 701 marked the company’s initial foray into the market
• IBM 650 it was designed as a logical upgrade to the existing punched card machines.

SECOND GENERATION
• 1959 marked the invention of transistors
• Faster input-output devices were also developed
• IBM Competitors: Burroughs, UNIVAC, NCR, CDC, and Honeywell, collectively known
as BUNCH
• 1963 marked the successful introduction to the market of minicomputers via Digital
Equipment Corporation’s PDP-8

THIRD GENERATION OF COMPUTERS

• 1967 arose the third generation of computer the invention of smaller electronic circuits
called integrated circuits
• IBM’s System 360 the first used computer in this generation
• Integrated circuit was composed of numerous transistors manufactured as a single unit

FOURTH GENERATION
• 4004 chip the First Microprocessor introduce by Intel Corporation
• A four bit processor with 2,200 transistors
• 1971 the fourth generation of computers.
• Altair 8800 1975 introduce computing to individuals and small companies
• 1981 IBM grab the lead in microcomputer industry through IBM PC (Personal
Computer)