3. FOUR BASIC PERIODS
CHARACTERIZED BY A PRINCIPAL TECHNOLOGY
USED TO SOLVE THE INPUT, PROCESSING, OUTPUT
AND COMMUNICATION PROBLEMS OF THE TIME:
• Pre-Mechanical
• Mechanical
• Electro-mechanical
• Electronic digital
4. PRE-MECHANICAL COMPUTING
1. Writing and Alphabets--communication.
• First humans communicated only through speaking and
picture drawings.
• 3000 B.C., the Sumerians in Mesopotamia devised cuneiform.
Cuneiform
2. Paper and Pens--input technologies.
About 2600 B.C., the Egyptians write on
the papyrus plant
Egyptians ‘ papyrus
5. PRE-MECHANICAL COMPUTING
3. Books and Libraries: Permanent Storage Devices
The Egyptians kept scrolls.
4. The First Numbering Systems
The first numbering systems similar to those in use today
were invented between 100 and 200 A.D. by Hindus in India who
created a nine-digit numbering system.
5. The First Calculators: The Abacus.
6. THE MECHANICAL AGE: 1450 - 1840
1. Movable metal-type printing by Johann
Gutenberg (1450)
2. Slide Rule by William Oughtred (1600s) 3. Pascaline by Blaise Pascal
A lot of new technologies were developed in this era due to an explosion of interest in
computation and information.
7. THE MECHANICAL AGE: 1450 -
1840
4. Gottfried Wilhelm von Leibnitz’s
Stepped Reckoner (1674)
5. Joseph-Marie Jacquard and his punched
card controlled looms (1804)
11. THE ELECTROMECHANICAL AGE: 1840 -
1940
The discovery of ways to harness electricity was the key
advance made during this period. Knowledge and information
could now be converted into electrical impulses.
17. THE ELECTRONIC AGE: 1940 - PRESENT.
These machines used electronic switches, in the form of vacuum tubes,
instead of the electromechanical relays seen in the previous era. In principle
the electronic switches would be more reliable, since they would have no
moving parts that would wear out, but the technology was still new at that
time and the tubes were comparable to relays in reliability
20. Eckert and Mauchly.
The First High-Speed, General-Purpose Computer Using Vacuum Tubes:
Electronic Numerical Integrator and Computer (ENIAC)
The ENIAC team (Feb 14, 1946). Left to right: J. Presper Eckert, Jr.; John Grist Brainerd; Sam Feltman;
Herman H. Goldstine; John W. Mauchly; Harold Pender; Major General G. L. Barnes; Colonel Paul N.
Gillon.
21. PROGRAMMING THE ENIAC
The Electronic
Numerical Integrator
and Computer
(ENIAC) was one of
the first general-
purpose electronic
digital computers, and
it was used to
integrate ballistic
equations and to
calculate the
trajectories of naval
shells. It was
completed in 1946 and
remained in use until
1955
22. EDVAC ((ELECTRONIC DISCRETE VARIABLE AUTOMATIC COMPUTER)
was the successor to ENIAC, and it was one of the
earliest stored-program computers, with the program
instructions held in memory.
23. UNIVERSAL AUTOMATIC COMPUTER (UNIVAC)
was the first general-purpose electronic digital computer design for business application produced in
the United States.[1] It was designed principally by J. Presper Eckert and John Mauchly, the inventors
of the ENIAC
25. FIRST GENERATION
COMPUTERS (VACUUM
TUBE BASED)
• The main characteristics of first generation of computers (1940s-
1950s)
• Main electronic component – vacuum tube
• Main memory – magnetic drums and magnetic tapes
• Programming language – machine language
• Power – consume a lot of electricity and generate a lot of heat.
• Speed and size – very slow and very large in size (often taking up
entire room).
• Input/output devices – punched cards and paper tape.
• Examples – ENIAC, UNIVAC1, IBM 650, IBM 701, etc.
• Quantity – there were about 100 different vacuum tube
computers produced between 1942 and1963.
26. SECOND GENERATION COMPUTERS
TRANSISTOR BASED
The main characteristics of second generation of
computers (1950s-1960s)
Main electronic component – transistor
Memory – magnetic core and magnetic tape / disk
Programming language – assembly language
Power and size – low power consumption, generated
less heat, and smaller in size (in comparison with the
first generation computers).
Speed – improvement of speed and reliability (in
comparison with the first generation computers).
Input/output devices – punched cards and magnetic
tape.
Examples – IBM 1401, IBM 7090 and 7094, UNIVAC
1107, etc.
27. THIRD GENERATION COMPUTERS
TRANSISTOR BASED
The main characteristics of third generation of
computers (1960s-1970s)
Main electronic component – integrated circuits
(ICs)
Memory – large magnetic core, magnetic tape /
disk
Programming language – high level language
(FORTRAN, BASIC, Pascal, COBOL, C, etc.)
Size – smaller, cheaper, and more efficient than
second generation computers (they were called
minicomputers).
Speed – improvement of speed and reliability
(in comparison with the second generation
computers).
Input / output devices – magnetic tape,
keyboard, monitor, printer, etc.
Examples – IBM 360, IBM 370, PDP-11,
UNIVAC 1108, etc.
28. FOURTH GENERATION COMPUTERS
MICROPROCESSOR BASED
The main characteristics of fourth generation of computers (1970s-present)
Main electronic component – very large-scale integration (VLSI) and
microprocessor.
VLSI– thousands of transistors on a single microchip.
Memory – semiconductor memory (such as RAM, ROM, etc.)
RAM (random-access memory) – a type of data storage (memory element) used in
computers that temporary stores of programs and data (volatile: its contents are
lost when the computer is turned off).
ROM (read-only memory) – a type of data storage used in computers that
permanently stores data and programs (non-volatile: its contents are retained
even when the computer is turned off).
Programming language – high level language (Python, C#, Java, JavaScript,
Rust, Kotlin, etc.).
A mix of both third- and fourth-generation languages
Size – smaller, cheaper and more efficient than third generation computers.
Speed – improvement of speed, accuracy, and reliability (in comparison with the
third generation computers).
Input / output devices – keyboard, pointing devices, optical scanning, monitor,
printer, etc.
Network – a group of two or more computer systems linked together.
Examples – IBM PC, STAR 1000, APPLE II, Apple Macintosh, etc.
29. FIFTH GENERATION COMPUTERS
ARTIFICIAL INTELLIGENCE BASED
The main characteristics of fifth generation of computers (the
present and the future)
Main electronic component: based on artificial intelligence, uses
the Ultra Large-Scale Integration (ULSI) technology and parallel
processing method.
ULSI – millions of transistors on a single microchip
Parallel processing method – use two or more microprocessors to
run tasks simultaneously.
Language – understand natural language (human language).
Power – consume less power and generate less heat.
Speed – remarkable improvement of speed, accuracy and
reliability (in comparison with the fourth generation computers).
Size – portable and small in size, and have a huge storage
capacity.
Input / output device – keyboard, monitor, mouse, trackpad (or
touchpad), touchscreen, pen, speech input (recognise voice /
speech), light scanner, printer, etc.
Example – desktops, laptops, tablets, smartphones, etc.
