Blaise Pascal*
 

French mathematician, physicist, and theologian.

Invented the first operational calculating machine in 1640 to help his father add sums of money.

The first operating model, the Arithmetic Machine, was introduced in 1642.

Joseph-Marie Jacquard

French silk weaver

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 early 1800s.

British mathematician, reformer, computer pioneer, economist, mechanical engineer, inventor.

Proposed building a machine called the Difference Engine to automatically calculate logarithmic and trigonometric functions tables in 1822.

Received a grant from the British government to build the engine in 1823. The engine was never fully completed.

Conceived the Analytical (Steam) Engine (early 1830s)  intended to use loops of Jacquard's punched cards to control an automatic calculator, which could make decisions based on the results of previous computations.  This machine was  intended to employ several features subsequently used in modern computers, including sequential control, branching, and looping.

Working with Babbage was Augusta Ada Lovelace, the daughter of the English poet Lord Byron. Ada, a superb mathematician and one of the few people who fully understood Babbage's vision, created a program for the Analytical Engine. Ada is now credited as being the first computer programmer and, in 1979, a modern programming language was named ADA in her honor.

 

George Boole

 

British mathematician.

Represented logical expressions in a mathematical form now known as Boolean Algebra (1847 and 1854).

Boolean Algebra  remained largely unknown and unused for the better part of a century, until a young student called Claude E. Shannon recognized its relevance to electronics design in 1938. In his paper, which was widely circulated, Shannon showed how Boole's concepts of TRUE and FALSE could be used to represent the functions of switches in electronic circuits.

Herman Hollerith

• American inventor
• Adapted Jacquard's punched cards to represent the American census data, and to then read and collate this data using an automatic machine.
• In addition to solving the census problem, Hollerith's machines proved themselves to be extremely useful for a wide variety of statistical applications, and some of the techniques they used were to be significant in the development of the digital computer.
• Formed his company Computing-Tabulating-Recording Co. in 1911.
• In February 1924, Hollerith's company changed its name to International Business Machines, or IBM.

John Vincent Atanasoff

• American mathematician and physicist.
• Constructed (with his graduate student Clifford Berry) the first truly electronic special-purpose digital computer in early 1939. The fate of this invention remain unclear.

• American engineer.
• Developed the first large-scale automatic digital computer based on relays known as the IBM automatic sequence controlled calculator (ASCC) or as the Harvard Mark I between 1939 and 1944.
• In 1947 Aiken predicted that only six electronic digital computers would be required to satisfy the computing needs of the entire United States.

• German engineer.
• Developed several digital computers based on relays starting in 1938 in Berlin.
• In 1943, Zuse started work on a general-purpose relay computer called the Z3 which was destroyed by bombing in 1944.
• His Z4 did survive (in a cave in the Bavarian Alps) and by 1950 it was up and running in a Zurich bank.

• British mathematician.
• In 1936 presented a 'paper' design for a machine that could solve any problem presented to it in symbolic form - 'The Turing Machine'.
• In January 1943, along with a number of colleagues, Turing began to construct an electronic machine to decode the German Geheimfernschreiber cipher.
• COLOSSUS, comprised 1,800 vacuum tubes and was completed and working by December of the same year.
• COLOSSUS was one of the world's earliest working programmable electronic digital computers. It was a special-purpose machine suited to a narrow range of tasks. Still it was flexible enough to be programmed to execute a variety of different routines.

John William Mauchly and J. Presper Eckert Jr.

• American physicist and engineer.
• Constructed the first true general-purpose electronic computer - the electronic numerical integrator and computer (ENIAC) at the University of Pennsylvania between 1943 and 1946.
• ENIAC  was 10 feet tall, occupied 1,000 square feet of floor space, weighed in at approximately 30 tons, and used more than 70,000 resistors, 10,000 capacitors, 6,000 switches, and 18,000 vacuum tubes. The final machine required 150 kilowatts of power, which was enough to light a small town.

Johann (John) Von Neumann

• Hungarian-American mathematician.
• Became aware of ENIAC in June 1944. Von Neumann was a consultant on the Manhattan Project and immediately recognized the role that could be played by a computer like ENIAC in solving the vast arrays of complex equations involved in designing atomic weapons.
• In June 1945, he published a paper, First Draft of a report to the EDVAC, in which he presented all of the basic elements of a stored-program computer (Von Neumann architecture):
• A memory containing both data and instructions. Also to allow both data and instruction memory locations to be read from, and written to, in any desired order.
• A calculating unit capable of performing both arithmetic and logical operations on the data.
• A control unit, which could interpret an instruction retrieved from the memory and select alternative courses of action based on the results of previous operations.
• Virtually all digital computers from that time forward have been based on this architecture.

 

• The military
• Big bureaucratic organizations: the Census Bureau, the Income Tax Office
• Universities
• Big corporations

* These are particularly important to remeber. However, keep in mind that the exam will cover the full content of these notes and your readings.