History of computers. Charles McAnany.. Abacus A simple, hand-held calculator. Developed by the Babylonians around 2400 BCE. Not programmable – simply.

History of computers.

Charles McAnany.

Abacus

• A simple, hand-held calculator.

• Developed by the Babylonians around 2400 BCE.

• Not programmable – simply a convenient way to store numbers.

http://upload.wikimedia.org/wikipedia/commons/e/ea/Boulier1.JPG

A Chinese abacus, or suanpan. Capable of addition, subtraction, Multiplication, division, square root, and cube root.

Programs.

• Medieval Islamic world saw the first programmable device – an automatic flute. If given notes to play, it would open the correct holes, so your fingers didn’t have to.

• In 1801, the Jacquard loom first used punched cards to store programs.

http://upload.wikimedia.org/wikipedia/commons/6/6c/Weaver.jpg

http://upload.wikimedia.org/wikipedia/commons/0/09/Jacquard.loom.cards.jpg

Difference engine• The first

programmable computer was Babbage’s difference engine. It took a description of a calculation to be performed, and performed it.

• In this sense, it is equivalent to a modern computer.

http://en.wikipedia.org/wiki/File:Babbage_Difference_Engine.jpg

http://upload.wikimedia.org/wikipedia/commons/d/d2/Charles_Babbage_1860.jpg

Electrification and tape

http://upload.wikimedia.org/wikipedia/commons/4/43/Cambridge_differential_analyser.jpg

http://upload.wikimedia.org/wikipedia/en/7/71/Honolulu_IFSS_Teletype1964.faa.jpg

Modern computers• Started by

WWII, in 1943. Finished in ‘46, shut down in ‘55.

• Programmable, entirely electric.

• Turing-complete

http://en.wikipedia.org/wiki/File:Eniac.jpg

Von-Neumann machines

• Equivalent to a Turing machine, but stores the program and data in one memory space. Most modern computers use this style of storage.

http://upload.wikimedia.org/wikipedia/commons/5/51/Magnetic_core.jpg

1955: The transistor

• A transistor is a switch that can be very, very small.

• In the late ‘60s, the microchip.

http://graphics.stanford.edu/~mcammara/hair/

1hair = 4,000 transistors

Altair 8800: The first home computer.

• Spawned the BASIC programming language, and Microsoft.

• Very modular.• Only differs from

modern computers by IO. http://en.wikipedia.org/wiki/File:Altair_8800_Computer.jpg

http://en.wikipedia.org/wiki/File:Cray-1-p1010221.jpg

http://en.wikipedia.org/wiki/File:Televideo925Terminal_adjusted.jpg

http://delong.typepad.com/sdj/2010/02/page/2/http://www.drajayjain.com/2010/11/hearing-aids-and-how-to-get-one.html