origins of digital computing
-earliest computing device
-first developed in Babylonia, over 5000 years ago and still used today in some parts of the world
-a "finger-powered pocket" calculator
Abacus
-used in science and engineering in 1600s until it was replaced in 1900s by pocket calculators
-manual calcultor
slide rule
mechanical calculators
since 1600s
-used punch cards to define complex patterns woven into textiles
jacquard loom (1801)
-piece of stiff paper with holes, where pressence or absence of holes in predefined positions to dictate the design of cloth.
-(later) digital data to be entered in computer was represented by the pressence o absence of holes in predefined positions(before the wide use of keyboard)
-later used to code computer programs
punch cards
-a restricted set of unambiguous instructions to solve a problem
-term is raised from the name of the 9th century mathematician Muhammed ibn Musa al-Khwarizmi
algorithm
- invented in 1918
-was the most soohisticated code system of its day
-a priority for the Allies to break ( Germans believed was unbreakable)
-contributed to the electronic computing machines jn 1940s that helped decrypt German coded messages
Enigma machine
-the 1st electronic digital general purpose computer
-commissioned by the US army for computing ballistic firing tables
-noted for massive scale and redundant design
-decimal internal coding
-operational in 1946
-manual programming of boards, switches and funtion table/ not Von neumann architecture
-early computer programming was slow, tedious and repetitous
ENIAC
Electronic Numerical Integrator And Computer