History of Computers
Critical thinking issues:
- differentiate between facts and values
- consider what something means to different people
- notice how what a technology does changes
Computers are a technology that has not been predictable but
rather has gone through several radical changes of
direction. Theme--what has shaped the evolution of computer
technology in these different directions (first military, then
business, then usability=computers can be useful to everyone)
What I want you to see first is that computers started as
something very different from what we have now. Can you
imagine what a computer would be if the internet didn't exist and
if there weren't any applications, you had to write your own
The Digital computer is an example of
the military-industrial-academic complex--it was invented out of
- need for ballistics calculations led to the
building of the Harvard Mark I and II using telephone
- Meanwhile in England Alan M. Turing ,
author of a famous paper in 1936 entitled "Can a Machine
Think" was building a specialized vacuum tube machine called
the Colossus for code-breaking, became operational in
1943. The program was built into the machine.
- Meanwhile John Brainard at the University of
Pennsylvania's Moore School of Electrical Engineering had been
doing ballistic calculations with an analog computer, and each
table took 30 days of machine time. Brainard proposed to
build a multipurpose electronic digital computer to compute
ballistic tables, and he got a contract from the Army
Ordinance Dept. (not OSRD) in 1943
- the army correctly judged that this technology
was so experimental that it was not likely to be completed in
time to be useful in the war.
- with the help of ideas from John Mauchly and
engineering by J. P. Eckert, Brainard built his machine and
named it the Electronic Numerical Integrator and Computer, or
ENIAC for short
- some of the original ideas had been developed
Atanasoff, a physicist at Iowa State College.
Maunchly visited in 1941 and asked permission to use some of
the features. Atanosoff asked for time to file a patent
application, but didn't get around to it because his wartime
assignment to work on analog computers took precedence.
In 1973 the courts did overthrow Maunchly's patent on the
basis of Atanosoff's precedence.
- When it was completed in late 1945, ENIAC
contained 18,000 vacuum tubes, was 100 feet long, 10 feet
high, and 3 feet deep and it consumed 140 kilowatts of
electricity in operation. At first it spend 50% of the
time under repair, but they got to a more acceptable one tube
failure every two days by leaving it on all the time (failures
had been happening mostly when during warm-up and
cool-down). It had been budgeted at $150,000 but ended
up costing nearly $500,000.
- ENIAC was 1000 times faster than the
electromechanical machines but it had only 20 words of storage
and it had to be programmed with wires (plugboards) and
- The first real problem programmed on ENIAC was
mathematical model of a hydrogen bomb from the Los
Alamos atomic weapons lab--thousands of steps and data on 1
million punched cards. The results showed several
problems with the proposed H-bomb design.
Hopper was hired from Harvard to lead the development of
programming. Most of the programming was done by the women
who had supervised the human calculators for two reasons:
programming the machine was not that different from parceling
out a complex series of calculations among a group of people
each of whom did one simple task, and the engineers were slow
to realize that programming was interesting and challenging.
projects led to a series of vacuum tube computers.
- In 1948 the first stored-program computer was
built in Manchester, England, confusingly called the Mark 1 .
- the next one at Penn was the Electronic
Discrete Variable Automatic Computer (EDVAC) built between
1947 and 1950, also with the ability to store programs
electronically. A copy in Cambridge, England, actually
operated first, and was described as the first stored-program
electronic computer with any serious computational ability.
- Eckert and Mauchley also built a commercial
the Census Bureau --the Universal Automatic Computer (UNIVAC)--eventually
sold. In November 1952 a UNIVAC computer was used to
correctly predict presidential election results, generating
much publicity. In England at about the same time
Ferranti built a commercial computer that became operational a
few months before UNIVAC and sold eight.
- John von Neumann, a Hungarian immigrant
working at Princeton's Institute for Advanced Studies, began
to collaborate with the Penn group in 1944, in particular
formulating the stored program concept. He then
developed a major research program at Princeton.
was built in 1944 and 1945 by Jay Forrester at MIT's
Lincoln Laboratory for the Air Force to simulate flight.
Forrester in 1949 introduced magnetic core storage for
- In 1955 IBM began producing computers designed
for business data-processing, building on existing technology
using punched cards.
Vacuum tubes could take you only so far
- but in research between 1945 and 1948, John
Bardeen, Walter Brattain, and William Shockley of Bell Labs
had invented the point-contact transistor.
- In the 1950s IBM,
and others used this new technology to produce medium to
large-scale systems--mainframe computers. IBM introduced
the first disk storage system in 1957. By 1960 they had an effective business system; they
produced 12,000 of the transistor based IBM 1401 computers,
most rented but the equivalent purchase price would have been
$150,000 each. They were popular partly because they
came with the best printer on the market. IBM beat out
its competitors by a decision in 1962 to go to a completely
new product line, the system 360. They spend $500,000 on
research and ten times as much on development, including
retooling factories and retraining staff
- these mainframe computers cost hundreds of
thousands to millions of dollars, required special housing and
air conditioning, and users submitted jobs on paper tape or
punched cards for batch processing. Remote job entry
(feed the cards into a card reader away from the mainframe
itself) was introduced in the 1960s.
of the history) :
- the earliest computers were programmed in
machine language--instructions and data input in binary
form. This was so awkward that it was fairly quickly
replaced by assembly language, which gave the computer its
actual instructions but allowed decimal numbers and relative
- In 1954 John Backus of IBM published the first
version of Fortran
(Formula Translator)--the first higher-level language.
By the mid-1960s 90% of all scientific and engineering
programs were written in Fortran.
- In 1959 COBOL was developed under the urging
of DoD as a standardized higher-level language for business
- these languages were essential to the wider
use of mainframe computers because they made programming
easier, but everything was still custom programmed.
- In 1961 MIT demonstrated a model time-sharing
system, and by the mid-1960s this had become a commercial
service. Terminals were Teletypes--already mass produced
and inexpensive for message communication, so you got your
output on paper, not on a screen.
teletype ASR33 used in timesharing
Integrated circuits and programming languages for
- mini-computers introduced by Digital
Equipment in 1963 taking advantage of integrated
circuits. The first one marketed, the PDP-5 sold for
$27,000 and two years later the PDP-8 was more powerful and
smaller and sold for $18,000. The PDP-8 was the first
mass-produced computer. By the 1970s minicomputers like
introduced in 1964, was designed for time-sharing on
minicomputers. Designed to be an easy-to-learn language,
compared to the technical knowledge presumed by Fortran.
- Pascal was released in 1971 as a language for
teaching programming and became a rival to BASIC
- mini-computers and BASIC meant that computers
could for the first time be used by people who were not
professional computer programmers. The first
applications were developed for mini-computers.
|languages & applications
|how computers were used
||wires, assembly language
|military research, census, weather
|higher level languages--Fortran
|scientific research, mathematical
problems , recordkeeping by big
businesses and government
word processors for offices (on
special purpose minicomputers)
|timesharing, text based games
, still mostly programs to make calculations,
wide use in universities
|applications become the usual way
of using computers, instead of programming
|games (but videogame machines are
cheaper), small businesses, education
Texas Instruments 2500 (1972)
- first patent to J.S. Kilby in 1959.
Introduced by Texas Instruments and Westinghouse in the early
1960s, came into real commercial use in 1964 with Fairchild
Semiconductors 702 linear IC.
- The first desktop electronic calculators were
introduced about 1963. In 1965 Texas
Instruments began work on a four-function pocket
calculator based on a single IC; they patented that
design. They had trouble getting their invention into
production--it came out in 1972 at $150 (the Japanese got
copies on the market as early as 1970).
- these had a more predictable market and got
more initial interest from big companies than the personal
computer. They also had a tremendously steep price
curve--by 1975 you could buy a 4-function calculator for under
- Integrated circuits were also used for
special-purpose word processors by Wang (1971) and IBM (the
the key step for the computer was the introduction
of the microprocessor:
- the idea of creating an entire simple computer
from integrated circuits began with amateurs
- The first microprocessor was the Intel 4004 in
Nov. 1971 and the 2 MHz 8080 in 1972. The 8080 was an 8
bit microprocessor that could access 64 k of memory.
- Atari ships Pong, the first
commercial video game, in 1972 (History of Home
- Scelbi Computer Consulting offered a kit
in 1973 for $565 with Intel's first microprocessor, the 8080,
and 1 kilobyte of memory
- In April 1975 Altair starts selling a kit
(called the Altair 8800) with a 8080 microprocessor and 1
kilobyte of memory for $375--users entered data in binary form
with 16 toggle switches and read the results in binary form on
an array of 16 pairs of panel lamps. Users had to
develop their own applications using machine language
Kildall was already at work writing the CP/M operating
- in 1975 a BASIC interpreter was demonstrated
on the Altair, and IBM introduces a 55 lb. luggable computer
with BASIC, 16 KB of RAM, and tape storage for the price of
- In June 1976 Southwest Technical Products
Company offered a machine with an editor and assembler, and
shortly afterwards with a BASIC interpreter. This
expanded the potential market, though it was still hobbyists,
and all sorts of small companies leapt into the business.
In 1977 the home computer began to move past the
- Apple II
and Commodore PET came
to the market in 1977--both included keyboard, game paddles,
BASIC in ROM, and storage of data via audiocassette
recorder. The Apple II cost $1300 and had 4 KB RAM--175
kits were sold in the first 10 months. The first model
didn't include a monitor--you hooked it to a TV set for
display. Only in Jan 1977 did Apple Computer move from
Steve Jobs's garage to an office.
- In Aug. Radio Shack announced the TRS-80
microcomputer with 4 KB RAM, keyboard, video display, and
tape cassette for $600--10,000 are sold in the first month.
- around the same time Bill Gates and Paul Allen
sign a partnership agreement to form Microsoft.
- these early microcomputers were mostly used
for games until the floppy disk became available as a low cost
data storage medium in the late 1970s--allowing the rapid
storage of 100 Kb of data.
- the 8086 microprocessor in 1978 had a speed of
4.77 MHz, 16 bit processing, and could access 1 MB of memory
- The first application was VisiCalc in
1979--the first spreadsheet--creating a business market.
Applewriter and Wordstar were released in the same year--they
had been preceded by Electric Pencil in 1977.
- In the 1979 fiscal year Apple sold 35,000
Apple II computers, 78,000 in 1980
- In 1981 the Osborne I was the
first complete portable microcomputer, with 64 K, two floppy
discs, the CP/M operating system, and BASIC for $1795.
- IBM got in the business (after much internal
resistance) and announced the IBM PC in 1981. The first
IBM PC cost $3000 and had the 8080 16 bit processor with a
speed of 4.77 MHz, 64 K of RAM, a floppy drive, monochrome
graphics, and the new DOS operating system, licensed from a
small company called Microsoft. Despite the fact that
better microprocessors were available IBM quickly came to
dominate the market.
- the most popular computer of the time was the
Commodore 64, introduced in 1982, which sold an estimated 22
million units. It had color graphics and 64 K of RAM and
cost only $400 (it hooked to a TV set for display) and was
used primarily for games.
- Lotus 1-2-3 introduced in 1982 was the killer
business application--the microcomputer became more than a
toy. dBase was the first data base program.
WordPerfect was introduced in 1984 and came to dominate the
business word processing market.
- Apple tried to compete with the IBM PC with
the Macintosh, introduced in 1984 at a price of $2495. A
revolutionary new way of using a computer, with a graphical
user interface, a mouse, and What-You-See-Is-What-You-Get word
- The IBM AT in 1985 went in a different
direction, with a speed of 6 MHz, 512 KB of RAM, and a 20 MB
hard drive for about $5000
- Commodore released the Amiga in 1985 with much
improved graphics and sound, but people didn't see any use for
it except for games.
- Windows was first released in 1985 but did not
earn a following until Windows 3 in 1990. Apple sued
Microsoft for copying the Macintosh user interface, but
lost. Windows represented a major change in the way
people used PCs.
Windows 286 (Windows 2)
For more details on the history of microcomputers I
become something completely different since the internet became
popular. Some people see the internet as leading us in a
very new direction: the internet as a self-organizing system, as
the last frontier
Good pages on this topic: The Roads and
Crossroads of Internet History
- anything can be put on the internet, so you have to
evaluate the information for yourself
- you don't have to publish, be recorded--anyone can share
their ideas and music
- is there some information that shouldn't be available?
- if music, etc. is freely distributed, how will artists
- what kinds of communities does the internet create?
- can/should the internet be regulated?
- is the purpose of the internet the sharing of
ideas or is the purpose selling stuff?
- how does it change knowledge, social
The very first beginning of the internet was a
system called ARPANET:
- in the late 1960s the development of
packet-switching networks make it much easier to send data
between computers by telephone line
- developed in a number of countries; in the US
particularly for for the Advanced Research Projects Agency of
the Dept of Defense in 1969. By 1971 this system had 15 nodes,
by 1972 37 nodes
- It was intended originally for remote
computing, but e-mail quickly caught on among those with
access, not only because of its speed but also because of its
was very important in the development of the Net.
- In its time it was the largest, fastest,
and most populated part of the Net.
- Its initial structure was influenced by
the fact that it was intended to form part of the central
command and control structure for the US armed forces
during the height of the Cold
War . As such, it was designed to be able to survive
a nuclear attack.
- This in turn influenced the decentralized
and peer-to-peer structure of the Net. ( Hardy,
History of the Net ).
- it was designed specifically to avoid
central control, so any part that survived could continue
number of internet hosts (source Hobbes
Internet Timeline ):
- in 1972 a conference drew up standards for
connecting networks such as ARPANET, the beginning idea of the
- in 1977 TheoryNet linked 100 computer science
researchers, leading to plans for to create a system that
could link all computer scientists. When NSF was brought
in for funding the decision was made to make the system
available without charge and gateway it to ARPANET, it opened
- in 1979 USENET
began--a system where many computers served as hosts storing a
series of documents.
- In 1986 this had grown so popular that
there was great controversy over a more organized naming
system ("The Great Renaming")
- Originally there was a centralized
backbone system, but when that backbone refused to carry a
new group called rec.sex alternate routes were devised
called alt. The backbone administrators gave up and
ever since Usenet has been proud of its anarchy.
- as of 1994 there were over 10,000 groups
- you can read Usenet via Google
Groups, though if you get serious about it you
should get a newsreader
- two years after USENET was created BITNET was
established to provide e-mail discussion lists.
- These had a more conservative culture and
generally banned flaming, which was seen as an art form on
USENET and in fact served as the main form of regulation.
- This kind of forum moved onto the internet
with the development of Listserv software; as of 1997
there were more than 70,000 different mailing lists.
- in 1983 MillNet was separated from ARPANET and
military control was relaxed on the ARPANET part. But it
didn't have central control
- in 1984 the installation of a name server
meant that you no longer had to specify the path to another
- in 1986 NSF Net encourages connection among
universities and reduced the attempts at central control that
had been exercised by ARPANET (which was abolished in
1989). Provided a faster backbone.
- in 1989 Compuserv was linked to the internet,
the first link by a commercial mail carrier
- in 1991 Gopher
was created by the Univ. of Michigan to provide access to mass
information--an interesting example of an innovation that
- in 1995 dial-up services began routinely
providing connection to the internet
- how long can you keep growing at a doubling
time of less about 18 months?
The World Wide Web (sources: About the World Wide Web ,
Internet Timeline ) :
- the idea of hypertext
--of documents with live links--dates back to the 1960s, first
on mainframes. Enthusiasts got very interested in how
knowledge might be communicated more effectively with
number of web sites:
- Tim Berners-Lee and other researchers at
CERN--a central European particle physics
laboratory--developed an internet hypertext system in the
- in 1993 Mosaic is introduced--an easy to
install browser which allows color images, and the WWW
launches immediately into explosive growth
- by 1994 the WWW was the second most-popular
service on the internet (after FTP) , by 1995
the most popular
- Internet communities developed for all sorts
of special interests
just wants to be free
- is the internet a way of showing off pictures
of your children, a way for people with common interests to
talk to teach other, or a revolutionary new way of doing
- the pornography industry pioneered
selling things over the internet
started selling books over the internet in July 1995 and was
the first internet-based business to get noticed
- by 1998 most mail order catalogs had web sites
where people could order products and most big businesses had
- internet users have been very resistant to paying
to use web sites, ending net neutrality may give businesses a
way around this
- can you make money by offering content for
free and carrying advertising?
- a lot of people were betting on it and so the
stock prices of internet firms went high, though few internet
businesses were making money. This led to a crash
- would you buy groceries over the
internet? Why and where E-business was succeeding
- Will the internet give the little
guy a chance? The web as a place for people to
express themselves is coming back again with weblogs
- are we loosing our privacy
creates new kinds of community
- Usenet was the first of these and still active--it can be
reached via Google
Groups. The interesting difference with Usenet is
that there is no way to kick someone out of a group. It has
mostly been replaced by Reddit
- Six Degrees in 1997 is considered the first social media
site--you could upload a profile and friend other users
- Bitnet was the first system of email groups
- Blogging started in 1999
- Discussion boards on the web have partially replaced
email groups, and now many groups are available in either
form--see for example Yahoo
- MySpace and Linked in grew in the very early 2000s
- Facebook was launched in 2004 initially only for people
at Harvard then at colleges and universities. It became
available to all in 2006, which is when Twitter was founded
- Instagram and Pinterest were founded in 2010, Google+ in
Three visions of what the
internet would be:
- a place to do business
- knowledge is power and now is available to everyone
- a community