The first computers were human "computers", predominantly women, who performed calculations by hand. Early mechanical aids included the abacus and Napier's Bones. The first programmable digital computer was the Harvard Mark I, built in 1944. The ENIAC, completed in 1946, was the first fully electronic general-purpose computer. The integrated circuit, invented in 1958, led to smaller, more powerful computers and the development of the microprocessor in the 1970s enabled personal computers. Bill Gates left Harvard to start Microsoft and write software for the Intel-based IBM PC, launched in 1981, which popularized personal computing.

1. THE HISTORY OF
COMPUTER
PREPARED BY:GILLEVILLE C. RICABORDA

2. The first computer were people.
“Computer “ was originally a job title
it was used to describe those human beings
(predominantly women) whose job it was to
perform the repetitive calculations
required to compute such things as
navigational tables, tide charts, and
planetary positions for astronomical
almanacs.

3. A typical computer operation back when computers were people.
This picture shows what were known as "counting tables

4. The abacus was an early aid for mathematical
computations. Its only value is that it aids the memory of
the human performing the calculation. . The abacus is often
wrongly attributed to China. In fact, the oldest surviving
abacus was used in 300 B.C. by the Babylonians. The abacus
is still in use today, principally in the far east.

5. In 1617 an eccentric Scotsman named John Napier invented
logarithms, which are a technology that allows
multiplication to be performed via addition.
The magic ingredient is the logarithm of each operand
, which was originally obtained from a printed table. But
Napier also invented an alternative
to tables , where the logarithm values were carved on ivory
sticks which are now called Napier's Bones.
An Original Napier’s Bones

6. Napier's invention led directly to the slide rule, first built
in England in 1632 and still in use in the 1960's by the
NASA engineers of the Mercury, Gemini, and Apollo
programs which landed men on the moon.

7. The first gear-driven calculating machine
to actually be built was probably
the calculating clock, so named by its
inventor, the German professor Wilhelm
Schickard in 1623.
This device got little publicity because
Schickard died soon afterward in the bubonic
plague.

8. In 1642 Blaise Pascal, at age 19,
invented the Pascaline as an aid
for his father who was a tax
collector. Pascal built 50 of this
gear-driven one-function
calculator (it could only add) but
couldn't sell many because of their
exorbitant cost and because they
really weren't that accurate (at
that time it was not possible to
fabricate gears with the required
precision)
. At the age of 12, he was discovered doing his version of Euclid's
thirty-second proposition on the kitchen floor.
Pascal went on to invent probability theory, the hydraulic press,
and the syringe.

9. Just a few years after Pascal, the German Gottfried Wilhelm Leibniz
(co-inventor with Newton of calculus) managed to build a four-function
(addition, subtraction, multiplication, and division) calculator that he
called the stepped reckoner .Leibniz was the first to advocate use
of the binary number system which is fundamental to the operation of
modern computers. Leibniz is considered one of the greatest of the
philosophers but he died poor and alone.

10. In 1801 the Frenchman Joseph Marie Jacquard invented a
power loom that could base its weave (and hence the
design on the fabric) upon a pattern automatically read
from punched wooden cards, held together in a long row
by rope. Descendents of these punched cards have been
in use ever since

11. • By 1822 the English mathematician Charles Babbage was
proposing a steam driven calculating machine the size of a
room, which he called the Difference Engine. This machine
would be able to compute tables of numbers, such as
logarithm tables.
•Ten years later the device was still nowhere near complete,
acrimony abounded between all involved, and funding
dried up. The device was never finished.

12. The census bureau offered a prize for an inventor to help
with the 1890 census and this prize was won by Herman
Hollerith, who proposed and then successfully adopted
Jacquard's punched cards for the purpose of computation.
Hollerith's invention, known as the Hollerith desk,
consisted of a card reader which sensed the holes in the
cards, a gear driven mechanism which could count
(using Pascal's mechanism which we still see in car
odometers), and a large wall of dial indicators (a car
speedometer is a dial indicator) to display the results of
the count.

13. IBM continued to develop mechanical calculators for sale
to businesses to help with financial accounting and inventory
accounting. One characteristic of both financial accounting
and inventory accounting is that although you need to
subtract, you don't need negative numbers and you really
don't have to multiply since multiplication can be
accomplished via repeated addition.

15. One of the four paper tape readers on the Harvard Mark I (you can observe the punched paper roll emerging from the bottom)
One early success was the Harvard Mark I computer which was built as a
partnership between Harvard and IBM in 1944. This was the first programmable
digital computer made in the U.S. But it was not a purely electronic computer.
Here's a close-up of one of the Mark I's four paper tape readers. A paper tape was
an improvement over a box of punched cards as anyone who has ever dropped --
and thus shuffled -- his "stack" knows.

16. One of the primary programmers for the Mark I was
a woman, Grace Hopper. Hopper found the first
computer "bug": a dead moth that had gotten into
the Mark I and whose wings were blocking the
reading of the holes in the paper tape. The word
"bug" had been used to describe a defect since least
1889 but Hopper is credited with the word
"debugging" to describe the work to eliminate program
faults.

17. In 1953 Grace Hopper invented the first high-level
language, "Flow-matic". This language eventually
became COBOL which was the language most affected
by the infamous Y2K problem. A high-level language is
designed to be more understandable by humans than is
the binary language understood by the computing
machinery. A high-level language is worthless without a
program -- known as a compiler -- to translate it into the
binary language of the computer and hence Grace
Hopper also constructed the world's first compiler.
Grace remained active as a Rear Admiral in the Navy
Reserves until she was 79. The Mark I operated on
numbers that were 23 digits wide. It could add or
subtract two of these numbers in three-tenths of a
second, multiply them in four seconds, and divide them
in ten seconds.

18. The microelectronics revolution is what allowed the
amount of hand-crafted wiring seen in the prior
photo to be mass-produced as an integrated circuit
which is a small sliver of silicon the size of your
thumbnail .
The primary advantage of an integrated circuit is not that
the transistors (switches) are miniscule (that's the
secondary advantage), but rather that millions of
transistors can be created and interconnected in a mass-
production process

19. • By the early 1980s this many transistors could
be simultaneously fabricated on an integrated
circuit. Today's Pentium 4 microprocessor
contains 42,000,000 transistors in this same
thumbnail sized piece of silicon. It's
humorous to remember that in between the
Stretch machine(which would be called a
mainframe today) and the Apple I a
computer)there was an entire industry
segment referred to as mini-computers such as the following
PDP-12 computer of 1969:
The DEC
PDP-12

20. • One of the earliest attempts to build an all-electronic (that is, no gears, cams,
belts, shafts, etc.) digital computer occurred in 1937 by J. V. Atanasoff, a
professor of physics and mathematics at Iowa State University. By 1941 he and
his graduate student, Clifford Berry, had succeeded in building a machine that
could solve 29 simultaneous equations with 29 unknowns. This machine was the
first to store data as a charge on a capacitor, which is how today's computers
store information in their main memory (DRAM or dynamic RAM
The Atanasoff-Berry Computer

21. •Another candidate for granddaddy of the modern computer was Colossus, built
during World War II by Britain for the purpose of breaking the cryptographic codes
used by Germany. Britain led the world in designing and building electronic
machines dedicated to code breaking, and was routinely able to read coded
Germany radio transmissions.
•The Harvard Mark I, the Atanasoff-
Berry computer, and the British
Colossus all made important
contributions. American and British
computer pioneers were still arguing
over who was first to do what, when
in 1965 the work of the German
Konrad Zuse was published for the
first time in English. Scooped! Zuse had
built a sequence of general purpose computers in Nazi Germany. The first, the Z1, was
built between 1936 and 1938 in the parlor of his parent's home.

22. ENIAC which stood for Electronic Numerical Integrator and Calculator. ENIAC was
built at University of Pennsylvania between 1943 and 1945 by two professors, John
Mauchly and the 24 year old J. Presper Eckert
ENIAC filled a 20 by 40 foot room, weighed 30 tons, and used more than
18,000 vacuum tubes. Like the Mark I, ENIAC employed paper card
readers obtained from IBM (these were a regular product for IBM, as
they were a long established part of business accounting machines,
IBM's forte). When operating, the ENIAC was silent but you knew it was
on as the 18,000 vacuum tubes each generated waste heat like a light
bulb and 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. Only the left half of ENIAC is visible in the
first picture, the right half was basically a mirror image of what's visible.

23. Even with 18,000 vacuum tubes, ENIAC could only hold 20 numbers
at a time. However, thanks to the elimination of moving parts it ran
much faster than the Mark I: 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.
Today's home computers employ clock speeds of 1,000,000,000
cycles per second. Built with $500,000 from the U.S. Army, ENIAC's
first task was to compute whether or not it was possible to build a
hydrogen bomb (the atomic bomb was completed during the war and
hence is older than ENIAC). The very first problem run on ENIAC
required only 20 seconds and was checked against an answer
obtained after forty hours of work with a mechanical calculator. After
chewing on half a million punch cards for six weeks, ENIAC did
humanity no favor when it declared the hydrogen bomb feasible. This
first ENIAC program remains classified even today

24. •Eckert and Mauchly's next teamed up with the
mathematician John von Neumann to design EDVAC, which
pioneered the stored program. Because he was the first to publish
a description of this new computer
•After ENIAC and EDVAC came other computers with humorous names
such as ILLIAC, JOHNNIAC, and, of course, MANIAC. ILLIAC was built at
the University of Illinois at Champaign-Urbana, which is probably why
the science fiction author Arthur. Clarke chose to have the HAL
computer of his famous book "2001: A Space Odyssey" born at
Champaign-Urbana. Have you ever noticed that you can shift each of
the letters of IBM backward by one alphabet position and get HAL?

25. ILLIAC II built at the University of Illinois (it is a good thing computers
were one-of-a-kind creations in these days, can you imagine being
asked to duplicate this?)

26. By the end of the 1950's computers were no longer one-of-a-kind hand
built devices owned only by universities and government research labs.
Eckert and Mauchly left the University of Pennsylvania over a dispute
about who owned the patents for their invention. They decided to set
up their own company. Their first product was the famous UNIVAC
computer, the first commercial (that is, mass produced) computer. In the
50's, UNIVAC (a contraction of "Universal Automatic Computer") was
the household word for "computer" just as
"Kleenex" is for "tissue".
The first UNIVAC was sold, appropriately
enough, to the Census bureau.
UNIVAC was also the first computer to
employ magnetic tape. Many
people still confuse a picture of a
reel-to-reel tape recorder with
a picture of a mainframe computer.
A reel-to-reel tape drive

27. • By 1955 IBM was selling more computers than UNIVAC and by the
1960's the group of eight companies selling computers was known as
"IBM and the seven dwarfs". IBM grew so dominant that the federal
government pursued anti-trust proceedings against them from 1969 to
1982 (notice the pace of our country's legal system). You might wonder
what type of event is required to dislodge an industry heavyweight.
In IBM's case it was their own decision to hire an unknown but
aggressive firm called Microsoft to provide the software for their
personal computer (PC). This lucrative contract allowed Microsoft to
grow so dominant that by the year 2000 their market capitalization
(the total value of their stock) was twice that of IBM and they were
convicted in Federal Court of running an illegal monopoly.

28. The IBM 7094, a typical
mainframe computer [photo
courtesy of IBM]
mainframe computers
There were 2 ways to interact with a mainframe. The first was
called time sharing because the computer gave each user a tiny sliver of
time in a round-robin fashion. Perhaps 100 users would be
simultaneously logged on, each typing on a teletype

29. • By the 1990's a university student would typically own his own
computer and have exclusive use of it in his dorm room. This
transformation was a result of the invention of the microprocessor.
A microprocessor (uP) is a computer that is fabricated on an
integrated circuit (IC). Computers had been around for 20 years
before the first microprocessor was developed at Intel .
•In 1971 In 1969 they were approached by Busicom, a Japanese
manufacturer of high performance calculators (these were type
writer sized units, the first sized scientific calculator was the Hewlett
-Packard HP35 introduced in 1972). Busicom wanted Intel to produce
12 custom calculator chips: one chip dedicated to the keyboard,
another chip dedicated to the display, another for the printer, etc.
But integrated circuits were (and are) expensive to design and this
approach would have required Busicom to bear the full expense of
developing 12 new chips since
these 12 chips would only be of use to them.

30. A Harvard freshman by the name of Bill Gates decided to drop out of
college so he could concentrate all his
time writing programs for this computer.
This early experienced put Bill Gates
In the right place at the right time once
IBM decided to standardize on the
Intel microprocessors for their line
of PCs in 1981. The Intel Pentium 4
used in today's PCs is still compatible with the
Intel 8088 used in IBM's first PC.

31. The invention of integrated circuit brought us the third generation of
computers. With this invention computers became smaller, more powerful more
reliable and they are able to run many different programs at the same time.
In1980 Microsoft Disk Operating System (MS-Dos) was born and in 1981 IBM
introduced the personal computer (PC) for home and office use. Three years
later Apple gave us the Macintosh computer with its icon driven interface and the
90s gave us Windows operating system.