A Brief History of Computers

Mechanical computers:

and his Difference Engine (1812) Mechanical From The Abacus 4000 BCE to Charles Babbage and his Difference Engine (1812)

Mechanical computers: The Abacus (c. 3000 BC)

1642: Blaise Pascal’s Pascaline

Blaise Pascal French philosopher and Mathematician Invented the Pascaline in 1642 Blaise Pascal

Pascaline Set of gears (similar to a clock) Addition only Device did not work properly

1694 Gottfried Leibniz’s Mechanical Calculator Step Reckoner

Gottfried Wilhelm von Leibniz German Mathematician 1671 introduced the Step Reckoner, a device which, as well as performing additions and subtractions, could multiply, divide, and evaluate square roots by series of stepped additions. Leibniz wheel – cylindrical wheel for the Stepped Reckoner. Stepped Reckoner was very unreliable.

Joseph-Marie Jacquard Punch card controlled looms (1804)

Punched Cards In the early 1800s, a French silk weaver called Joseph-Marie Jacquard invented a way of automatically controlling the warp and weft threads on a silk loom by recording patterns of holes in a string of cards. In the years to come, variations on Jacquard's punched cards would find a variety of uses, including representing the music to be played by automated pianos and the storing of programs for computers

Preparing the cards with the pattern for the cloth to be woven

Charles Babbage The Father of Computers

Charles Babbage Father of Computing 1822 a British mathematician and inventor Charles Babbage try to create the Difference Engine. Difference Engine was never created. Ideals of the Difference Engine led up to the Analytical Engine.

Difference Engine

Analytical Engine Created by Charles Babbage in 1833 Used punch cards for set of instructions Was never built The design served as a model for the modern computer.

Charles Babbage Analytical Engine

Lady Augusta Ada Countess of Lovelace Daughter of the famous English poet Lord Byron, and trained in mathematics and science Became colleague of Babbage after hearing about his ideas for “Analytic Engine” at a dinner party Predicted in 1843 many uses for engine and developed first “programs” for it

Ada Lovelace Daughter of the famous English poet Lord Byron, and trained in mathematics and science Became colleague of Babbage after hearing about his ideas for “Analytic Engine” at a dinner party Predicted in 1843 many uses for engine and developed first “programs” for it

Ada Byron Augusta Ada Byron (Lovelace) was born December 10, 1815 A mathematician and scientist. Ada suggested to Babbage writing a plan for how the engine might calculate Bernoulli numbers. This plan, is now regarded as the first "computer program." A software language developed by the U.S. Department of Defense was named "Ada" in her honor in 1979.

Electro-mechanical computers From Herman Hollerith’s 1890 Census Counting Machine to Howard Aiken and the Harvard Mark I (1944)

Herman Hollerith and his Census Tabulating Machine (1884)

Hollerith’s Tabulating Machine Created for a contest by the U.S Census Bureau Invented by Herman Hollerith in 1890 Used electricity instead of gears to perform calculations Used punch card to program it

A closer look at the Census Tabulating Machine

Herman Hollerith Hollerith, Herman (1860-1929), American inventor, born in Buffalo, New York, and educated at Columbia University, who devised a system of encoding data on cards through a series of punched holes. This system proved useful in statistical work and was important in the development of the digital computer. Hollerith's machine, used in the 1890 U.S. census, "read" the cards by passing them through electrical contacts. Closed circuits, which indicated hole positions, could then be selected and counted. His Tabulating Machine Company (1896) was a predecessor to the International Business Machines Corporation (IBM).

The Harvard Mark I (1944) Calculator (ASCC) Howard Aiken

Mark I Created by IBM in 1944 Howard Aiken of Harvard assisted IBM Used relay switches and punched cards Mark I was not considered a computer (calculator)

Mark I The Mark I was constructed out of switches, relays, rotating shafts, and clutches, and was described as sounding like a "roomful of ladies knitting." The machine contained more than 750,000 components, was 50 feet long, 8 feet tall, and weighed approximately 5 tons!

The first computer bug Rear Admiral Dr. Grace Murray Hopper

Grace Murray Hopper Grace Brewster Murray Hopper was born in New York City on December 9, 1906, to Walter Fletcher Murray and Mary Campbell Horne Murray. At age seven, she showed a particular love for gadgets, disassembling seven alarm clocks in the attempt to determine how they worked. Hopper's parents provided a strong foundation for her inquisitiveness. She shared her love of math with her mother, who studied geometry by special arrangement when serious study of math was still thought improper for a woman. Her father, a successful insurance broker despite the double amputation of his legs, encouraged all his children, through his speech and example, that they could do anything if they put their minds to it. Hopper's first assignment was under Commander Howard Aiken at the Bureau of Ordinance Computation at Harvard University. There she became the third programmer of the Mark I, the world's first large-scale automatically sequenced digital computer. The computer was used to calculate aiming angles for Naval guns in varying weather conditions. Because the numbers were so pertinent, Hopper and her assistants were often required to run and monitor the system twenty-four hours a day. They spent countless hours transcribing and inputting codes for Mark I and its successors, Mark II and III. Hopper received the Naval Ordnance Development Award in 1946 for her work on the Mark series. During her work with Mark II, Hopper was credited with coining the term "bug" in reference to a glitch in the machinery.

Electronic digital computers From John Vincent Atanasoff’s 1939 Atanasoff-Berry Computer (ABC) to the present day

Alan Turing The Turing Machine in 1936 Alan developed the idea of a Universal Machine . He envisioned a computer that could perform many tasks by simply changing the program instead of components.

Iowa State University, Ames, IA John Atanasoff Physics Prof At Iowa State University, Ames, IA JOHN VINCENT ATANASOFF was born on 4 October 1903 a few miles west of Hamilton, New York. His father was a Bulgarian immigrant named Ivan Atanasov. His last name was changed to Atanasoff by immigration officials at Ellis Island when he arrived with an uncle in 1889, and later on, his first name was changed to John.

The Atanasoff-Berry Computer (ABC) The first electronic computer built between 1939 –1942. Created by John Atanasoff and Clifford Berry at Iowa State University Used the Binary System (1’s and 0’s) Used Vacuum Tubes and switches Did not get recognized until 50 years later

Clifford Edward Berry PhD student of Dr. Atanasoff’s was born in Gladbrook, Iowa on April 19, 1918 to Fred Gordon Berry and Grace Strohm. He was the oldest of four children born to the couple: Clifford, Keith, Frederick, and Barbara.

)) The ABC was the first electronic digital computer, invented by John Vincent Atanasoff

ENIAC Created by John Mauchly and J. Presper Eckert in 1943 ENIAC – Electronic Numerical Integration and Calculator Built at the Univ. of Pennsylvania

1946 The ENIAC John Presper Eckert (1919-1995) and --Electronic Numerical Integrator and Computer John Presper Eckert (1919-1995) and John Mauchly (1907-1980) of the University of Pennsylvania Moore School of Engineering

The ENIAC: Electronic Numerical Integrator and Computer 30 tons, 18,000 vacuum Tubes (little powerful than the modern Calculator)

John von Neumann Created the CPU which stored programs so you won’t have to flip switches or pull wires to change instructions

Vonn Neuman Architecture Stored Program Computer Programmable Instruction Set Architecture Memory bandwidth

UNIVAC UNIVersal Automatic Computer Used stored programs Built by Mauchley and Eckert Sold to the U.S Census Bureau in 1951.

Transistor Invented by William Shockley, John Bardeen, and Walter Brittain in 1947. The invention of the transistor made computers smaller and less expensive and increased calculating speed to up to 10,000 calculations per second.

Generation 3: Post-1960 Jack St. Clair Kilby's and Robert Noyce's independent invention of the integrated circuit Invention of the microprocessor, by Ted Hoff and Federico Faggin at Intel. Steve Wozniak, co-founder of Apple Computer, is credited with developing the first mass-market home computers.

Stephen Wozniak & Steve Jobs