Chapter 1: Computer System: Evolution of Computer
Generations of computer
Generation | Time Period | Technology Used | Examples | Key Features |
First Generation | 1945 – 1955 | Very large in size, consumed huge electricity, generated lots of heat, machine language only, slow processing. | ||
Second Generation | 1956 – 1964 | IBM 1401, IBM 7094, CDC 1604 | Smaller, faster, more reliable than vacuum tubes, assembly language, less heat, better storage. | |
Third Generation | 1965 – 1971 | Integrated Circuits (ICs) | Smaller in size, more efficient, faster, supported high-level programming languages (COBOL, FORTRAN), better multitasking. | |
Fourth Generation | 1971 – 1980s/90s | 1972-1980 | Microprocessors (VLSI) | Intel 4004, IBM PC, Apple Macintosh | Personal computers introduced, very small and powerful, GUI-based operating systems, widespread use, networking started. |
Fifth Generation | 1980s – Present & Beyond | Artificial Intelligence (AI), ULSI, Parallel Processing, Quantum Computing (emerging) | Robots, Neural Networks, Modern AI systems (e.g., IBM Watson, Google AI), Smartphones | Focus on AI and machine learning, natural language processing, cloud computing, quantum computing research, portability, super speed. |
1. First generations computer (1945-1955)
· They used vacuum tubes as their basic electronic components used to control and amplify electronic signals.
· They were big in size, consume more electricity and generate large amount of heat thus required air conditioning system to keep device cool.
· They were unreliable and were prone to frequent hardware failure.
· They were normally not used for commercial purpose.
· Machine level language was used to program these computers.
eg: ENIAC, EDVAC, EDSAC, UNIVAC
2. Second generations computer (1956-1964 )
· They used transistors as their basic electronic components.
· They were small in size as compared to first generation thus consume less electricity and generate less heat.
· They were less prone to hardware failure thus more reliable.
· They were not also for commercial purpose because production was difficult and costly.
· Assembly language were used to program these computers.
eg: IBM 7000, IBM 1401, IBM 1620, NCR 304, MARK III, ATLAS
3.Third generations computer ( 1965-1971 )
· They used Integrated Circuits (IC) as their basic electronic components.
· They were smaller in size, consume less electricity and generate less amount of heat.
· They were faster and more reliable compared to first and second generations.
· They were widely used for the commercial application all over the world.
· High level language were used to program these computers.
eg: PDP-8, PDP-11, ICL 2900 series, IBM 360, IBM 370
4. Fourth generation computer (1972-1980)
· They use VLSI ( Very Large Scale Integrated Circuits ) as their main electronic components.
· There size were drastically reduced and hence were they were much more portable.
· They were faster in processing and were much more reliable.
· They have larger memory up to GB and TB.
· They use different advance high level language to program this computer.
eg: Apple Macintosh, IBM PC
5. Fifth generation computer (1980-onwards)
· They use ULSIC (Ultra Large Scale Integrated Circuit) or Microprocessor as their major electronic components.
· They have or will have artificial intelligence.
· They have tremendously high processing unit due to parallel processing.
· They are capable of image processing, speech or voice recognition.
· They use different high level language to program this computer.
Evolution & History
|
Early
Counting Tools |
Abacus
(\~3000 BC); Napier’s Bones; Slide Rule. These represent the very early
mechanical methods of calculation. |
|
Jacquard
Loom |
Invented
by Joseph Marie Jacquard. Used punched cards to control textile looms; early
idea of programmability. |
|
Charles
Babbage’s Machines |
Difference
Engine (1822) and Analytical Engine (\~1833). Introduced ideas of input,
output, memory, programmability. Considered the foundation of modern
computers. |
|
Ada
Lovelace |
Often
called the first computer programmer; wrote algorithms for Babbage’s
machines. |
|
Tabulating
Machines |
Herman
Hollerith’s punch card tabulating machine used in census work; eventually led
to formation of companies like IBM. |
|
First
Electronic Computers |
ENIAC,
EDVAC, UNIVAC etc. Introduction of stored-program concept (Von Neumann
architecture). |
Measurement of
Speed & Storage Units
1 Byte (B) = 8 bits
1 Kilobyte (KB) = 1024 Bytes
1 Megabyte (MB) = 1024 KB
1 Gigabyte (GB) = 1024 MB
1 Terabyte (TB) = 1024 GB
1 Petabyte (PB) = 1024 TB
To convert between units, you either multiply or divide
by 1024,
depending on the direction:
Small
→ Big (B → KB → MB → GB …) → Divide by 1024
Big → Small (GB → MB → KB → B …) → Multiply by
1024
Examples
1.
Convert 2048 KB to MB
2048 / 1024 = 2 MB
2.
Convert 5 GB to MB
5 * 1024 = 5120 MB
3.
Convert 1 TB to GB
1 * 1024 = 1024 GB
Exercises
Multiple
Choice Questions:
a.
The
name of first computer designed by Charles Babbage is..... a)
i.
Analytical
Engine
ii.
Difference
Engine
iii.
Calculator
iv.
EDSAC
b.
Which
was the first electronics digital programmable computing device?
i.
ENIAC
ii.
EDVAC
iii.
EDSAC
stands for
iv.
EDSAC
c.
EDSCA
stands for…
i.
Electronic Delay
Storage Automatic Calculator
ii.
Electronic
Delay Storage Automatic Computer
iii.
Electronic
Data Storage Automatic Calculator
iv.
Electronic
Data Storage Automatic Computer
d.
Which was the first commercial computer?
i.
Mark 1
ii.
Analytical
Engine
iii.
Difference
Engine
iv.
Colossus
e.
John
Mauchly and J. P. Eckert are the inventors of computer.
i.
UNIAC
ii.
ENIAC
iii.
EDSAC
iv.
Mark
1
f.
Who
invented the punch card?
i.
Semen
Korsakov
ii.
Charles
Babbage
iii.
Joseph Marie
Jacquard
iv.
Herman
Hollerith
g.
Which
electronic components are used in First Generation Computers?
i.
Transistors
ii.
Integrated
Circuits
iii.
Vacuum Tubes
iv.
Microprocessor
h.
Which
electronic components are used in Fifth Generation Computers?
i.
Transistors
ii.
Integrated
Circuits
iii.
ULSI Microprocessor
iv.
VLSI
Microprocessor
i.
ENIAC Computer belongs to
i.
First Generation
Computers
ii.
Second
Generation Computers
iii.
Third
Generation Computers
iv.
Fourth
Generation Computers
j.
…. is used as a programming language in first
generation computers?
i.
FORTRAN
ii.
COBOL
iii.
BASIC
iv.
Machine Language
2.
Short Answer Questions:
a)
Why is Charles Babbage known as father of computer science? Explain with his
invention.
Charles
Babbage is called the Father of Computer Science because he designed the first
mechanical computers. His inventions include:
Difference Engine (1822): For solving
mathematical tables.
Analytical Engine (1837): Considered the first
design of a general-purpose computer (with input, memory, CPU, and output).
b)
Draw the figure of Abacus showing its parts.
c)
Write the feature of Mark-I.
·
First
electromechanical computer (1944).
·
51
feet long and 8 feet high.
·
Could
perform addition, subtraction, multiplication, and division automatically.
·
Very
slow compared to modern computers.
d)
Why Lady Augusta Ada Lovelace called first programmer?
Ada
Lovelace is called the first programmer because she wrote the first algorithm
(set of instructions) to be executed by Babbage’s Analytical Engine, making her
the world’s first computer programmer.
e)
Define tabulating machine. Write its use.
A
tabulating machine was invented by Herman Hollerith in 1890.It used punched
cards to store and process data.
Its
use: Mainly for census and statistical calculations.
f)
How are computer generation classified?
Computer
generations are classified based on:
·
Technology
used (vacuum tubes, transistors, ICs, microprocessors, AI chips).
·
Size
and speed.
·
Programming
languages used.
·
Storage
capacity and processing power.
g)
What is computer generation? List the different generation of computers.
Computer generation refers to the stages of computer
development with major technological improvements.
Generations:
1. First Generation (1940–1956) – Vacuum
tubes.
2. Second Generation (1956–1963) –
Transistors.
3. Third Generation (1964–1971) – Integrated
Circuits (ICs).
4. Fourth Generation (1971–1980s) –
Microprocessors.
5. Fifth Generation (1980s–Present) – AI,
ULSI, supercomputers.
h)
Define first generation of computers and write its two drawbacks.
First
generation computers (1940–1956) used vacuum tubes as the main electronic
component.
Drawbacks:
·
Very
large in size and produced a lot of heat.
·
Slow
speed and required high maintenance.
i)
Mention the feature of fourth generation computers.
·
Used
microprocessors (VLSI chips).
·
Much
faster and smaller in size.
·
Portable
and reliable.
·
Use
of high-level languages like C, C++.
·
Low
cost and widely available.
j)
Write the features of fifth generation computer.
·
Based
on ULSI & AI (Artificial Intelligence).
·
Very
high speed with parallel processing.
·
Natural
language processing (e.g., voice recognition).
·
Portable,
lightweight, and user-friendly.
·
Used
in robotics, expert systems, and machine learning.
k)
Differentiate between the third generation computers and fourth generation
computers.
|
Third
Generation |
Fourth
Generation |
|
Used
Integrated Circuits (ICs). |
Used
Microprocessors (VLSI). |
|
Larger
in size compared to 4th gen. |
Much
smaller and portable. |
|
Processing
speed in microseconds. |
Processing
speed in nanoseconds. |
|
Supported
only limited multiprogramming. |
Advanced
OS, multiprogramming, networking. |
3.
Long Answer Questions:
a)
Explain the history of computing device of mechanical era.
The
mechanical era (before the invention of modern electronic computers) saw the
development of different devices that helped in calculation. Some major
developments were:
1.
Abacus (3000 BC):
First
known calculating device, invented in China.
Used
beads on rods to perform addition, subtraction, multiplication, and division.
2.
Napier’s Bones (1617):
Invented by John Napier.
A set
of rods with numbers used for multiplication and division.
3.
Pascal’s Calculator (1642):
Invented by Blaise Pascal.
A
mechanical device using gears and wheels to perform addition and subtraction.
4.
Leibniz’s Calculator (1671):
Invented by Gottfried Leibniz.
Improved Pascal’s design; could perform
multiplication, division, and square roots.
5.
Jacquard’s Loom (1801):
Invented by Joseph Marie Jacquard.
Used
punched cards to control weaving patterns, later inspiring data storage
systems.
6.
Difference Engine (1822):
Designed by Charles Babbage to calculate
mathematical tables automatically.
7.
Analytical Engine (1837):
Also
by Charles Babbage.
Considered the first concept of a
general-purpose computer with input, memory, processor, and output.
b)
Compare and discuss between electromechanical and electronic computers.
|
Feature |
Electromechanical
Computers |
Electronic
Computers
|
|
Technology |
Used
mechanical parts and electrical relays.
|
Used
electronic components like vacuum tubes, transistors, ICs, and
microprocessors. |
|
Speed |
Very
slow (operations in seconds).
|
Much
faster (operations in microseconds or nanoseconds). |
|
Size |
Large
and bulky due to mechanical parts.
|
Smaller
and compact compared to electromechanical. |
|
Reliability |
Less
reliable due to wear and tear of moving parts. |
Highly
reliable, no moving parts. |
|
Examples |
Harvard
Mark I, Zuse Z3.
|
ENIAC,
EDVAC, EDSAC. |
|
|
|
|
Electromechanical
computers were the bridge between mechanical calculators and modern computers.
The shift to electronic computers brought a revolution in speed, reliability,
and usability, leading to today’s advanced systems.
c)
Describe the history of computer in Nepal in your own words.
The
development of computers in Nepal started much later compared to developed
countries. Important points:
1.
First Computer (1971):
Nepal
received its first computer IBM 1401 to process census data of 1971 at National
Computer Center (NCC).
2.
1980s Expansion:
Computers started being used in government
offices, banks, and large organizations.
Training programs were started to build IT
manpower.
3.
1990s Development:
Personal computers (PCs) became available in
Nepal.
Internet introduced in Nepal in 1994 (by Royal
Nepal Academy of Science and Technology - RONAST).
Computer education began in schools and
colleges.
4.
2000s to Present:
Widespread use of computers in business,
education, health, and communication.
Growth of IT companies, software development,
and outsourcing industry.
Government introduced IT policies to promote e-Governance,
e-Banking, and digital literacy.
In
summary, the history of computers in Nepal began with census processing in
1971, and now computers are an essential part of daily life, business, and
national development.
Exercises
Multiple
Choice Questions:
a.
The
name of first computer designed by Charles Babbage is..... a)
i.
Analytical
Engine
ii.
Difference
Engine
iii.
Calculator
iv.
EDSAC
b.
Which
was the first electronics digital programmable computing device?
i.
ENIAC
ii.
EDVAC
iii.
EDSAC
stands for
iv.
EDSAC
c.
EDSCA
stands for…
i.
Electronic Delay
Storage Automatic Calculator
ii.
Electronic
Delay Storage Automatic Computer
iii.
Electronic
Data Storage Automatic Calculator
iv.
Electronic
Data Storage Automatic Computer
d.
Which was the first commercial computer?
i.
Mark 1
ii.
Analytical
Engine
iii.
Difference
Engine
iv.
Colossus
e.
John
Mauchly and J. P. Eckert are the inventors of computer.
i.
UNIAC
ii.
ENIAC
iii.
EDSAC
iv.
Mark
1
f.
Who
invented the punch card?
i.
Semen
Korsakov
ii.
Charles
Babbage
iii.
Joseph Marie
Jacquard
iv.
Herman
Hollerith
g.
Which
electronic components are used in First Generation Computers?
i.
Transistors
ii.
Integrated
Circuits
iii.
Vacuum Tubes
iv.
Microprocessor
h.
Which
electronic components are used in Fifth Generation Computers?
i.
Transistors
ii.
Integrated
Circuits
iii.
ULSI Microprocessor
iv.
VLSI
Microprocessor
i.
ENIAC Computer belongs to
i.
First Generation
Computers
ii.
Second
Generation Computers
iii.
Third
Generation Computers
iv.
Fourth
Generation Computers
j.
…. is used as a programming language in first
generation computers?
i.
FORTRAN
ii.
COBOL
iii.
BASIC
iv.
Machine Language
2.
Short Answer Questions:
a)
Why is Charles Babbage known as father of computer science? Explain with his
invention.
Charles
Babbage is called the Father of Computer Science because he designed the first
mechanical computers. His inventions include:
Difference Engine (1822): For solving
mathematical tables.
Analytical Engine (1837): Considered the first
design of a general-purpose computer (with input, memory, CPU, and output).
b)
Draw the figure of Abacus showing its parts.
c)
Write the feature of Mark-I.
·
First
electromechanical computer (1944).
·
51
feet long and 8 feet high.
·
Could
perform addition, subtraction, multiplication, and division automatically.
·
Very
slow compared to modern computers.
d)
Why Lady Augusta Ada Lovelace called first programmer?
Ada
Lovelace is called the first programmer because she wrote the first algorithm
(set of instructions) to be executed by Babbage’s Analytical Engine, making her
the world’s first computer programmer.
e)
Define tabulating machine. Write its use.
A
tabulating machine was invented by Herman Hollerith in 1890.It used punched
cards to store and process data.
Its
use: Mainly for census and statistical calculations.
f)
How are computer generation classified?
Computer
generations are classified based on:
·
Technology
used (vacuum tubes, transistors, ICs, microprocessors, AI chips).
·
Size
and speed.
·
Programming
languages used.
·
Storage
capacity and processing power.
g)
What is computer generation? List the different generation of computers.
Computer generation refers to the stages of computer
development with major technological improvements.
Generations:
1. First Generation (1940–1956) – Vacuum
tubes.
2. Second Generation (1956–1963) –
Transistors.
3. Third Generation (1964–1971) – Integrated
Circuits (ICs).
4. Fourth Generation (1971–1980s) –
Microprocessors.
5. Fifth Generation (1980s–Present) – AI,
ULSI, supercomputers.
h)
Define first generation of computers and write its two drawbacks.
First
generation computers (1940–1956) used vacuum tubes as the main electronic
component.
Drawbacks:
·
Very
large in size and produced a lot of heat.
·
Slow
speed and required high maintenance.
i)
Mention the feature of fourth generation computers.
·
Used
microprocessors (VLSI chips).
·
Much
faster and smaller in size.
·
Portable
and reliable.
·
Use
of high-level languages like C, C++.
·
Low
cost and widely available.
j)
Write the features of fifth generation computer.
·
Based
on ULSI & AI (Artificial Intelligence).
·
Very
high speed with parallel processing.
·
Natural
language processing (e.g., voice recognition).
·
Portable,
lightweight, and user-friendly.
·
Used
in robotics, expert systems, and machine learning.
k)
Differentiate between the third generation computers and fourth generation
computers.
|
Third
Generation |
Fourth
Generation |
|
Used
Integrated Circuits (ICs). |
Used
Microprocessors (VLSI). |
|
Larger
in size compared to 4th gen. |
Much
smaller and portable. |
|
Processing
speed in microseconds. |
Processing
speed in nanoseconds. |
|
Supported
only limited multiprogramming. |
Advanced
OS, multiprogramming, networking. |
3.
Long Answer Questions:
a)
Explain the history of computing device of mechanical era.
The
mechanical era (before the invention of modern electronic computers) saw the
development of different devices that helped in calculation. Some major
developments were:
1.
Abacus (3000 BC):
First
known calculating device, invented in China.
Used
beads on rods to perform addition, subtraction, multiplication, and division.
2.
Napier’s Bones (1617):
Invented by John Napier.
A set
of rods with numbers used for multiplication and division.
3.
Pascal’s Calculator (1642):
Invented by Blaise Pascal.
A
mechanical device using gears and wheels to perform addition and subtraction.
4.
Leibniz’s Calculator (1671):
Invented by Gottfried Leibniz.
Improved Pascal’s design; could perform
multiplication, division, and square roots.
5.
Jacquard’s Loom (1801):
Invented by Joseph Marie Jacquard.
Used
punched cards to control weaving patterns, later inspiring data storage
systems.
6.
Difference Engine (1822):
Designed by Charles Babbage to calculate
mathematical tables automatically.
7.
Analytical Engine (1837):
Also
by Charles Babbage.
Considered the first concept of a
general-purpose computer with input, memory, processor, and output.
b)
Compare and discuss between electromechanical and electronic computers.
|
Feature |
Electromechanical
Computers |
Electronic
Computers
|
|
Technology |
Used
mechanical parts and electrical relays.
|
Used
electronic components like vacuum tubes, transistors, ICs, and
microprocessors. |
|
Speed |
Very
slow (operations in seconds).
|
Much
faster (operations in microseconds or nanoseconds). |
|
Size |
Large
and bulky due to mechanical parts.
|
Smaller
and compact compared to electromechanical. |
|
Reliability |
Less
reliable due to wear and tear of moving parts. |
Highly
reliable, no moving parts. |
|
Examples |
Harvard
Mark I, Zuse Z3.
|
ENIAC,
EDVAC, EDSAC. |
|
|
|
|
Electromechanical
computers were the bridge between mechanical calculators and modern computers.
The shift to electronic computers brought a revolution in speed, reliability,
and usability, leading to today’s advanced systems.
c)
Describe the history of computer in Nepal in your own words.
The
development of computers in Nepal started much later compared to developed
countries. Important points:
1.
First Computer (1971):
Nepal
received its first computer IBM 1401 to process census data of 1971 at National
Computer Center (NCC).
2.
1980s Expansion:
Computers started being used in government
offices, banks, and large organizations.
Training programs were started to build IT
manpower.
3.
1990s Development:
Personal computers (PCs) became available in
Nepal.
Internet introduced in Nepal in 1994 (by Royal
Nepal Academy of Science and Technology - RONAST).
Computer education began in schools and
colleges.
4.
2000s to Present:
Widespread use of computers in business,
education, health, and communication.
Growth of IT companies, software development,
and outsourcing industry.
Government introduced IT policies to promote e-Governance,
e-Banking, and digital literacy.
In
summary, the history of computers in Nepal began with census processing in
1971, and now computers are an essential part of daily life, business, and
national development.