1. History of Computers and
its effects
Jeremy Hart

2. Early inventions
• Used to mean humans who performed calculations
• Abacus – 7 rings on rods, 2 for hands, 5 for fingers, that is used as an aid for
calculations; invented by Babylonians in 300 B.C.E.
• Logarithms – Allows multiplication to be made by addition, by use of operands on
a table; invented by Scotsman John Napier in 1617
• Slide rule – Led directly from logarithms; invented by English in 1632, and used by
NASA in the 1960’s
• Calculating clock – Gear-driven calculating machine; invented by German professor
Wilhelm Schickard in 1623
• Pascaline – A one-function calculator (adds), and same mechanism is used in
odometers; invented by Blaise Pascal in 1642

3. Four-function calculators and
punched card
• Stepped reckoner – A four-function calculator invented
by German Gottfried Wilhelm Leibniz a few years after
the Pascaline; consisted of fluted drums having ten flutes
arranged around their circumference in a stair-step
fashion (binary number system)
• Punched cards - power loom that could base its weave
upon a pattern automatically read from punched
wooden cards, held together in a long row by rope;
invented by Frenchman Joseph Marie Jacquard in 1801

4. Charles Babbage
• Difference engine – Steam driven calculating machine proposed by
Babbage, which would be able to compute tables of numbers;
never finished
• Analytic Engine – As large as a house and powered by 6 steam
engines, and would be programmable because of punched cards
• Innovations of the engine – Used to represent an abstract idea;
used as a storage unit; had two parts, “Store” and “Mill”, which are
now “memory unit” and “central processing unit (CPU)”; had a
conditional statement, which allows a program to achieve different
results each time it is run

5. Herman Hollerith
• Hollerith desk – Consisted of a card reader which sensed the holes in the cards, a
gear driven mechanism which could count, and a large wall of dial indicators (used
in speedometers) to display the results of the count; was used to help sped up the
census; invented in 1890
• Read/write – The punching (write) of new cards based upon an analysis (reading)
of some other set of cards. Complicated analyses, too involved to be accomplished
during a single pass thru the cards, could be accomplished via multiple passes thru
the cards using newly printed cards to remember the intermediate results.
Different than read-only, when a tapestry was designed and then were not
changed.
• IBM (International Business Machines) – Founded by Hollerith, and first called
Tabulating Machine Company; made punch cards for things like bills, toll booths,
ballots, and formerly Social Security and other checks

6. (Harvard) Mark 1
• First programmable digital computer, as a partnership between Harvard and IBM
in 1944
• Constructed out of switches, relays, rotating shafts, and clutches. The machine
weighed 5 tons, incorporated 500 miles of wire, was 8 feet tall and 51 feet long,
and had a 50 ft. rotating shaft running its length, turned by a 5 horsepower electric
motor. The Mark I ran non-stop for 15 years, sounding like a roomful of ladies
knitting.
• Shaft was the central power source; paper tape readers were an improvement to
the punched cards
• Had the first computer “bug”, a dead moth whose wings were blocking the reading
of the paper tape; also the first “debugging”
• Inspired the high-level language “Flow-matic”, which is now COBOL, designed to
be understandable more to humans than computers; also inspired the compiler, a
program to translate it into the binary language of the computer
• Operated on numbers 23 digits wide, and add or subtract two numbers in 3/10 of
a second, multiply in 4 seconds, and divide in 10. Now can add in a billionth of a
second. Could store 72 numbers; RAM today can store 30 million numbers

7. After the Mark 1
• Apple 1 – A home computer sold for $600; invented in 1976
• CDC 7600 – Very expensive because of the tons of required hand assembly
• Microelectronics revolution - Allowed a large amount of hand-crafted
wiring to be mass-produced as an integrated circuit which is a small sliver
of silicon the size of your thumbnail
• Integrated circuit – The millions of transistors (switches) are miniscule and
can be created and interconnected in a mass-production process. All the
elements on the integrated circuit are fabricated simultaneously by a small
number of optical masks that define the geometry of each layer, which
speeds up the process of fabricating the computer and reduces its cost
• IBM stretch – This computer possible because of the micro-electronics
revolution; 33 feet long; had 150,000 transistors, and required individual
assembly invented in 1959; today’s Pentium 4 microprocessor contains 42
million transistors in same size silicon piece
• The Stretch (mainframe) and Apple 1 (desktop computer) are mini-
computers, like the PDP-12 computer invented in 1969

8. Back to World War 2
• J.V. Atanasoff – Tried to build all electronic computer in 1937, but in 1941, he
and Clifford Berry built a machine that could solve 29 equations with 29
unknowns; it could store data as charge on a capacitor, used today in main
memory (DRAM); first to use binary arithmetic; however, not programmable
and no conditional branch
• Colossus – Built during WWll by Britain to break the cryptographic codes used
by Germany; led the world in designing and building electronic machines
dedicated to code breaking, and was routinely able to read coded Germany
radio transmissions
• Konrad Zuse – Built a sequence of general purpose computers in Nazi
Germany; the first, Z1, was built between 1936-38 in his parent’s home; the
third, Z3, built in 1941, was probably the first operational, general-purpose,
programmable (that is, software controlled) digital computer; had an
arithmetic unit to do the calculations, a memory for storing numbers, a control
system to supervise operations, and input and output devices to connect to
the external world; also the first high-level computer language, "Plankalkul"

9. The ENIAC
• Built between 1943 and 1945 by two professors, John Mauchly and J. Presper Eckert
• Filled a 20 by 40 foot room, weighed 30 tons, and used more than 18,000 vacuum
tubes; employed paper card readers; was silent; the 18,000 vacuum tubes each
generated waste heat like a light bulb; all this heat (174,000 watts of heat) meant that
the computer could only be operated in a specially designed room with its own heavy
duty air conditioning system
• To reprogram, had to rearrange the patch cords, and the settings of 3000 switches; to
program a modern computer, you type out a program with statements like:
• Circumference = 3.14 * diameter; to perform this computation on ENIAC you had to
rearrange a large number of patch cords and then locate three particular knobs on that
vast wall of knobs and set them to 3, 1, and 4.
• A multiplication that required 6 seconds on the Mark I could be performed on ENIAC in
2.8 thousandths of a second; ENIAC's basic clock speed was 100,000 cycles per second,
while today it is 1 billion cycles a second
• John von Neumann helped design EDVAC, which pioneered the stored program.; the
program (sequence of computation steps) could be represented electronically just as
the data was.

10. After the ENIAC
• General protection fault/blue screen of death- modifications happen as fast as
computers compute, and could modify themselves as they ran; faulty logic in program
could cause it to damage itself
• Reprogramming – Allows it to do a wide variety of events, including special effects,
music download, car tire rotation techniques, and writing style of Shakespeare’s work
• UNIVAC – First commercial computer, built in the 50’s; means “Universal Automatic
Computer”; first to employ magnetic tape
• IBM became dominant company; “IBM and the seven dwarfs”; hired Microsoft to
provide software for personal computer (PC); by 2000 their market capitalization was
twice IBM; mainframe computers came in 70’s, like IBM 7090, IBM 360, IBM 370
• Time share - Giving the user a tiny sliver of time in round fashion, with up to 100 user
logged in, typing on a teletype, which is a motorized typewriter that could transmit
keystrokes to mainframe and print response on paper (type single text line, hit carriage
return, and wait for it to print);
• Binary numbers (0-1); easy to control, sense, make; either hole is punched or not;
vacuum tubes replaced by transistors
• Batch mode processing – Full attention to programming; have to run it off-line on a key
punch machine which generates punch cards; university students bought blank cards;
one card holds one program statement, and submitted program by stackiing cards

11. 1990’s to Present
• In the 90’s, a university student would usually own his own computer and
have exclusive use of it in dorm room
• Microprocessor (uP) – A computer that is fabricated on an integrated
circuit (IC); first developed at Intel in 1971; put an entire computer on a
chip; made a general purpose chip which could be reprogrammed for
different tasks
• Program - A sequence of instructions stored in memory
• Intel – Made the Intel 4004, the first uP, which had 2300 transistors and
has speed of 108 kHz; was on the Pioneer 10 spacecraft; then made 8008
and 8080 (the 8080 was employed in MITS Altair, the first PC); Pentium 4
has 42 million transistors and clock rate of 2 GHz
• Busicom – Made a desk calculator, but went out of business
• Bill Gates – Created Microsoft; dropped out of college, at same time IBM
standardized Intel uP for line of PCs in 1981; Pentium 4 is still compatible
with 8088

12. Effects of computers on
society, science, and technology
• Everybody uses a computer for countless reasons,
whether for info, games, videos, communication, work,
or for any other reason.
• They are important for science, to analyze data, do
complicated calculations, and research the topics.
(Helps eliminate human error)
• It is almost all technology, whether an I-pad, I-pod, X-
box, TV, PSP, Reader, car, or a regular computer or
laptop. The are used in all space missions now, and
especially for things to dangerous for a human to do.
Robots are possible because of computers.

13. Bibliography
• http://www.computersciencelab.com/Comput
erHistory/History.htm