Computer is an electronic device that manipulates information, or data. It has the ability to store, retrieve, and process data
Computer is a machine that manipulates data according to a list of instructions (program)
Computer is any device which aids humans in performing various kinds of computations or calculations
Three principal characteristics of computer
It responds to a specific set of instructions in a well-defined manner
It can execute a pre-recorded list of instructions
It can quickly store and retrieve large amounts of data
The first use of the word "computer" was recorded in 1613, referring to a person who carried out calculations, or computations, and the word continued to be used in that sense until the middle of the 20th century
Tally stick
An ancient memory aid device to record and document numbers, quantities, or even messages
Abacus
A mechanical device used to aid an individual in performing mathematical calculations. Invented in Babylonia in 2400 B.C. and first used in China in around 500 B.C. Used to perform basic arithmetic operations
Napier's Bones
Invented by John Napier in 1614. Allowed the operator to multiply, divide and calculate square and cube roots by moving the rods around and placing them in specially constructed boards
Slide Rule
Invented by William Oughtred in 1622. Based on Napier's ideas about logarithms. Used primarily for multiplication, division, roots, logarithms, and trigonometry. Not normally used for addition or subtraction
Pascaline
Invented by Blaise Pascal in 1642. Limited to addition and subtraction. Too expensive
Stepped Reckoner
Invented by Gottfried Wilhelm Leibniz in 1672. A machine that can add, subtract, multiply and divide automatically
Jacquard Loom
A mechanical loom, invented by Joseph-Marie Jacquard in 1881. An automatic loom controlled by punched cards
Arithmometer
A mechanical calculator invented by Thomas de Colmar in 1820. The first reliable, useful and commercially successful calculating machine that could perform the four basic mathematic functions. The first mass-produced calculating machine
Difference Engine and Analytical Engine
Automatic, mechanical calculators designed to tabulate polynomial functions. Invented by Charles Babbage in 1822 and 1834. The first mechanical computer
First Computer Programmer
In 1840, Augusta Ada Byron suggests to Babbage that he use the binary system. She writes programs for the Analytical Engine
Scheutzian Calculation Engine
Invented by Per Georg Scheutz in 1843. Based on Charles Babbage's difference engine
Tabulating Machine
Invented by Herman Hollerith in 1890. To assist in summarizing information and accounting. The first printing calculator
Harvard Mark 1
Also known as IBM Automatic Sequence Controlled Calculator (ASCC). Invented by Howard H. Aiken in 1943. The first electro-mechanical computer
Z1
The first programmable computer. Created by Konrad Zuse in Germany from 1936 to 1938. To program the Z1 required that the user insert punch tape into a punch tape reader and all output was also generated through punch tape
Atanasoff-Berry Computer (ABC)
The first electronic digital computing device. Invented by Professor John Atanasoff and graduate student Clifford Berry at Iowa State University between 1939 and 1942
ENIAC
ENIAC stands for Electronic Numerical Integrator and Computer. It was the first electronic general-purpose computer. Completed in 1946. Developed by John Presper Eckert and John Mauchly
UNIVAC 1
The first commercial computer. Designed by John Presper Eckert and John Mauchly
EDVAC
EDVAC stands for Electronic Discrete Variable Automatic Computer. The First Stored Program Computer. Designed by Von Neumann in 1952. It has a memory to hold both a stored program as well as data
Osborne 1
the first portable computer. Released in 1981 by the Osborne Computer Corporation
Electronic Controls Company
The first computer company founded in 1949 by John Presper Eckert and John Mauchly
Four Stages of Information Technology Development
Premechanical (3000 B.C. - 1450 A.D.)
Mechanical (1450 - 1840)
Electromechanical (1840 - 1940)
Electronic (1940 - present)
Pre-Mechanical Age: 3000 B.C. - 1450 A.D.
Writing and Alphabets-communication
Books and Libraries: Permanent Storage Devices
The First Numbering Systems
The First Calculators: The Abacus
Mechanical Age: 1450 – 1840
The First Information Explosion
Calculating Machine
Pascaline
Babbage's Engines
Electromechanical Age: 1840 - 1940
Morse Code: 1835
Telephone and Radio: 1876
Comptograph: 1885
Punch Card: 1890
Electronic Age: 1941 - Present
Z1: 1941
Mark I: 1942
ABC Computer: 1942
Generations of Computer
First generation - 1946 to 1958
Second generation - 1959 to 1964
Third generation - 1965 to 1970
Fourth generation - 1971 to Today
Fifth generation - Today to future
The development of the integrated circuit was a milestone in the third generation of computers
First generation computers
Used vacuum tubes for circuitry and magnetic drums for memory
Were often enormous, taking up entire rooms
Were very expensive to operate
Used a great deal of electricity
Generated a lot of heat, which was often the cause of malfunctions
Second generation computers
Transistors replaced vacuum tubes
One transistor replaced the equivalent of 40 vacuum tubes
Allowed computers to become smaller, faster, cheaper, more energy-efficient and more reliable
Still generated a great deal of heat that can damage the computer
Third generation computers
Development of the integrated circuit
Transistors were miniaturized and placed on silicon chips, called semiconductors
Drastically increased the speed and efficiency of computers
Could carry out instructions in billionths of a second
Much smaller and cheaper compare to the second-generation computers
Fourth generation computers
The microprocessor brought the fourth generation
Thousands of integrated circuits were built onto a single silicon chip
Became more powerful and could be linked together to form networks
Led to the development of the Internet
Fifth generation computers
Based on Artificial Intelligence (AI)
Still in development
Use of parallel processing and superconductors
Aim to develop devices that respond to natural language input and are capable of learningand self-organization
Some applications like voice recognition are being used today
Applications of ICT (Computers) in Our Daily Lives