Ten Interesting Computer Scientists

1
Ten Interesting Computer Scientists

• Dr. Raymond Greenlaw
• Armstrong Atlantic State University
• School of Computing

2
Outline

• History of Computer Science
• John Backus
• Stephen Cook
• Seymour Cray
• Edsger Dijkstra
• Bill Gates
• Alan Kay
• Donald Knuth
• Leslie Lamport
• John McCarthy
• Alan Turing

3
History of Computer Science

• 1673 Gottfried Wilhelm von Leibniz invents a
  machine to do multiplication
• 1821 Charles Babbage builds a machine to
  calculate exponential functions, begins designing
  Analytical Engine
• 1832 Ada Lovelace begins writing programs (on
  punch cards) for the nonexistent Analytical
  Engine, inventing such concepts as loops and
  subroutines
• 1935 Alan Turing defines a model for computation

4
History of Computer Science

• 1937 Claude Shannon links Boolean logic to
  digital circuit design
• 1939 Turings work plays a key role in breaking
  the Germans Enigma code machine
• 1943 Small computers are being built in
  multiple countries
• 1950 Turing proposes a test of machine
  intelligence, the Turing test
• 1956 John McCarthy coins the term artificial
  intelligence

5
History of Computer Science

• 1957 FORTRAN is released by John Backus and the
  IBM team
• 1958 John McCarthy invents Lisp
• 1959 John Backus and Peter Naur propose the use
  of context-free grammars to describe programming
  languages
• 1961 Edsger Dijkstra applies the semaphore
  principle used in train signaling systems to
  mutual exclusion in computer operations

6
History of Computer Science

• 1962 Donald Knuth begins work on The Art of
  Computer Programming
• 1971 Alan Kay develops the first
  object-oriented programming language, Smalltalk
• 1971 Stephen Cook publishes a paper on
  non-deterministic polynomial completeness
  (NP-completeness), defining a new family of
  problems that is not computable in a practical
  sense

7
History of Computer Science

• 1973 Leonid Levin publishes a paper identifying
  the class of NP-complete problems independently
  of Cook (research was conducted in 1971)
• 1977 Leslie Lamport defines a model of time for
  distributed systems based on a partial order of
  events
• 1980 Microsoft is founded, helping to push PCs
  into widespread use with the public

8
John Backus

• We simply made up the language as we went along.
  We did not regard language design as a difficult
  problem, merely a simple prelude to the real
  problem designing a compiler which could produce
  efficient programs...

9
Biography - John Backus

• 1949 Graduated from Columbia University with a
  B.S. in Mathematics
• 1950 Joined IBM and worked on the SSEC
  (Selective Sequence Electronic Calculator) for
  three years
• Collaborated with Peter Naur to create
  Backus-Naur Form
• Developed FP which helped push functional
  programming
• Retired in 1991

10
Achievements - John Backus

• Designer of FORTRAN
• Backus-Naur Form
• Designed FP, a functional programming language
• 1977 Turing Award winner
• 1987 named an IBM Fellow
• 1993 awarded a Draper Prize

11
Trivia - John Backus

• Has a plate in his head of his own design after
  having a bone tumor
• Roughly half the work of designing FORTRAN went
  into generating efficient machine code
• After retiring in 1991, has completely withdrawn
  from computer science
• Practices meditation

12
Stephen Cook

• The idea that there wont be an algorithm to
  solve itthis is something fundamental that wont
  ever changethat idea appeals to me.

13
Biography - Stephen Cook

• 1961 B.S. in Mathematics from University of
  Michigan
• 1962, 1966 M.S. and Ph.D. in Mathematics from
  Harvard
• 1966-1970 Assistant Professor, University of
  California, Berkeley
• 1970 Joined University of Toronto as Associate
  Professor, Professor in 1975, and University
  Professor of Computer Science and Mathematics in
  1985

14
Achievements - Stephen Cook

• Formalized the notion of NP-completeness
• Cooks Theorem concerns itself with reducing
  NP-complete problems to a general Satisfiability
  problem
• 1977 Steacie Fellowship
• 1982 Turing Award winner
• Fellow of Royal Society of Canada

15
Seymour Cray

• "If you were plowing a field, which would you
  rather use Two strong oxen or 1024 chickens?"

16
Biography - Seymour Cray

• 1950 B.S. in Electrical Engineering, University
  of Minnesota
• 1951 Awarded a M.S. in Applied Mathematics,
  University of Minnesota
• 1950 Joined Engineering Research Associates
• 1960 Joined Control Data Corporation
• 1965 The CDC 6600, the first commercial
  supercomputer, is released
• 1972 Founded Cray Research

17
Biography - Seymour Cray

• 1976 The Cray-1 is released
• 1980 Cray steps down as CEO of Cray Research
  and becomes an independent contractor
• 1989 Founded Cray Computer Corporation
• 1995 Set up SRC Computers, Inc
• 1996 Died in a car accident

18
Achievements - Seymour Cray

• Founder of Cray Research and Cray Computer
  Corporation
• Released the first commercial supercomputer
• Designed computers concerned with total computing
  speed
• Worked hard to improve I/O bandwidth as opposed
  to just concentrating on processor speed

19
Trivia - Seymour Cray

• The vehicle Cray was driving when he died, a Jeep
  Cherokee, was designed on a Cray supercomputer
• In 1986, Apple bought a Cray X-MP and announced
  it would be used to design the next Macintosh,
  Cray replied that he was using a Macintosh to
  design the Cray-2 supercomputer

20
Edsger Dijkstra

• "Computer Science is no more about computers than
  astronomy is about telescopes."

21
Biography - Edsger Dijkstra

• Studied physics at the University of Leiden
• 1970s Worked as a research fellow for Burroughs
  Corporation
• Worked at the Eindhoven University of Technology
  in the Netherlands
• Held the Schlumberger Centennial Chair in
  Computer Sciences at the University of Texas at
  Austin
• Retired in 2000
• Died August 6, 2002

22
Achievements - Edsger Dijkstra

• Dijkstras algorithm (shortest path) which has
  been used to solve numerous routing problems
• The semaphore construct which helped solve the
  problem of critical regions
• Formulated the dining philosophers problem
• 1972 Turing Award winner
• Has archive of technical papers at University of
  Texas at Austin

23
Trivia - Edsger Dijkstra

• At age 12, attended Gymnasium Erasminium, an
  elite Dutch high school
• Go To Statement Considered Harmful was the
  revised title by Niklaus Wirth (then editor of
  CACM), originally titled A case against the goto
  statement
• On team to invent first compiler for ALGOL 60,
  made a deal with collaborator not to shave until
  project was complete, kept the beard until his
  death

24
Trivia - Edsger Dijkstra

• Dining Philosophers
• Imagine that five philosophers are sitting around
  a table. Before each is a bowl of rice and a
  chopstick to either side of the bowl. The rules
  for dining
• Each philosopher thinks for a while, eats for a
  while, and then waits for a while
• To eat, he must hold both his right and left
  chopstick
• They only communicate by lifting and lowering
  their chopsticks

25
Trivia - Edsger Dijkstra

• Dining Philosophers
• In order to eat, the following algorithm must be
  utilized
• Pick up the right chopstick when available (wait
  if right neighbor has it)
• Pick up the left chopstick when available (wait
  if left neighbor has it)
• Eat
• Using this algorithm, a few scenarios can occur
  leading to certain situations

26
Trivia - Edsger Dijkstra

• Dining Philosophers
• Deadlock occurs when all philosophers decide to
  eat at the same time, they succeed at the first
  step, but wait forever at the second
• Starvation can occur for other philosophers if
  one philosopher never releases his chopsticks
• Even if all eat, some may eat more than others
  which can cause lack of fairness

27
Bill Gates

• "The best way to prepare to be a programmer is
  to write programs, and to study great programs
  that other people have written. In my case, I
  went to the garbage cans at the Computer Science
  Center and fished out listings of their operating
  system."

28
Biography - Bill Gates

• 1975 Founded Microsoft with Paul Allen after
  developing a version of BASIC that ran on Altair
  systems
• 1976 Wrote an article denouncing people who
  used software and didnt pay for it, helped push
  closed-source development, after openly admitting
  he took source code from dumpsters
• 1980 Sold IBM a relabeled version of QDOS,
  known as PC-DOS

29
Biography - Bill Gates

• Early 1980s Aggressively marketed MS-DOS to PC
  clone manufacturers
• Late 1980s Microsoft Windows began to be
  preinstalled on a number of PCs
• 1990 Windows 3.0 is released
• 1998 Gates steps down as CEO of Microsoft, but
  continues to serve as Chairman of the Board and
  Chief Software Architect

30
Achievements - Bill Gates

• Helped port BASIC to the Altair
• Co-founded Microsoft with Paul Allen
• Chairman and Chief Software Architect of
  Microsoft
• Provided a GUI operating system to many PC clone
  manufacturers
• Has positioned Microsoft as the leading software
  company in the world

31
Trivia - Bill Gates

• Dropped out of Harvard in his third year to
  pursue software development
• Attained the rank of Life Scout in the Boy Scouts
  of America
• Named wealthiest person in the world by Forbes
  magazine for several years
• Has a house in Washington valued at over 113
  million, all visitors get a microchip that
  adjusts temperature and other conditions to their
  preferences

32
Alan Kay

• All understanding begins with our not accepting
  the world as it appears.

33
Biography - Alan Kay

• 1966 B.S. in Mathematics and Molecular Biology,
  University of Colorado
• 1969 M.S. in Electrical Engineering, Ph.D. in
  Computer Science, University of Utah
• 1970 Professor, Stanford Artificial
  Intelligence Laboratory
• 1972 Group Leader, Xerox Palo Alto Research
  Center
• 1984 Apple Fellow, Apple Computers

34
Achievements - Alan Kay

• Designer of Smalltalk
• Coined the term object-orientation
• Conceived the laptop computer
• Architect of the modern windowing GUI
• 2001 UdK 01-Award winner
• 2003 Turing Award winner
• 2004 Kyoto Prize and Charles Stark Draper Prize
  winner

35
Trivia - Alan Kay

• Could read by the age of three
• Expelled from Bethany College for protesting the
  Jewish quota
• Made a living as a professional guitarist in the
  1960s
• Used his degree in molecular biology to help form
  the basic ideas of OOP
• Very interested in using computers to further
  education

36
Donald Knuth

• Computer programming is an art form, like the
  creation of poetry or music.

37
Biography - Donald Knuth

• In 8th grade, won competition by composing words
  from Zieglers Giant Bar Knuth found 4,500 in
  two weeks of feigning illness, the judges master
  list had 2,500, has said he would have found more
  if he had thought to use the apostrophe
• Graduated from high school in 1956 with the
  highest GPA ever achieved at that school

38
Biography - Donald Knuth

• Graduated in 1960 from Case Institute of
  Technology with a B.S. in Mathematics, was
  simultaneously awarded an M.S. for his
  achievements, an unprecedented move
• Received a Ph.D. in Mathematics from California
  Institute of Technology in 1963
• Joined Stanford University as a Professor of
  Computer Science in 1968
• In 1993, became Professor Emeritus of The Art of
  Computer Programming at Stanford, where he is
  still currently located

39
Achievements - Donald Knuth

• Authored The Art of Computer Programming, a
  multi-volume tome on CS
• Inventor of TeX and METAFONT
• LR(k) parsing
• Knuth-Morris-Pratt algorithm
• 1974 Turing Award winner
• 1979 National Medal of Science
• 1995 John von Neumann Medal

40
Trivia - Donald Knuth

• The Art of Computer Programming began as a text
  about compilers
• Loves organ music, mostly 4 and 8-hand music
  which he plays on an organ in his home, he
  studied piano as a child
• Pays 2.56 (one hexadecimal dollar) for errors
  found in his books
• Quit using email in 1990
• Processes all communications in batch-mode

41
Leslie Lamport

• A distributed system is one in which the failure
  of a computer you didnt even know existed can
  render your own computer unusable.

42
Biography - Leslie Lamport

• 1960 B.S. in mathematics, Massachusetts
  Institute of Technology
• 1963 M.A., Brandeis University
• 1972 Ph.D., Brandeis University
• 1970-1977 Massachusetts Computer Associates
• 1977-1985 SRI International
• 1985-2001 Digital Equipment Corporation/Compaq
• 2001-Present Works for Microsoft

43
Achievements - Leslie Lamport

• Bakery Algorithm an improvement to Djikstras
  semaphore idea, which involves each participant
  getting a ticket
• Lamport Clocks A relative time idea used in
  distributed computing
• Developed a technique using digital signatures to
  aid in fault-tolerant systems
• Designer/developer of LaTeX, a macro system that
  sits on top of Knuths TeX and is used by many
  scientists for papers

44
Trivia - Leslie Lamport

• LaTeX started as a side project to improve the
  new version of TeX introduced in 1982, Lamport
  estimates he spent about 10 months developing
  LaTeX
• Very modest about his involvement with many of
  his ideas, saying most of it seems like dumb
  luckI happened to be looking at the right
  problem, at the right time, having the right
  background.

45
John McCarthy

• If you want the computer to have general
  intelligence, the outer structure has to be
  commonsense knowledge and reasoning.

46
Biography - John McCarthy

• 1948 B.S. in Mathematics from the California
  Institute of Technology
• 1951 Ph.D. in Mathematics from Princeton
• Short-term appointments at Princeton, Stanford,
  Dartmouth, and MIT
• 1962 Full Professor at Stanford University
• Retired at the end of 2000, is now Professor
  Emeritus

47
Achievements - John McCarthy

• Coined the term artificial intelligence in 1955
  at the Dartmouth Conference
• Designer of LISP, the principle language of
  artificial intelligence
• 1961 First to propose publicly the selling of
  computing as a utility, like electricity or water
• 1962 Set up the Stanford AI Laboratory
• 1971 Turing Award winner

48
Trivia - John McCarthy

• As a high school junior, bought the calculus
  books used for freshman and sophomore math,
  worked out all the exercises which allowed him to
  skip the first two years of math when he attended
  the school in 1944
• Like Backus and Kay, eventually lost control over
  the language (LISP) he invented

49
John McCarthy

• LISP list processing language
• All lists are contained within parentheses (A B
  C), with the elements as atoms
• Supports recursion and has an eval operation to
  define new functions and execute them as part of
  that program
• CAR returns the first element of the list, (CAR
  (A B C)) returns A
• CDR returns a list with everything but the first
  element, (CDR (A B C)) returns (B C)

50
Alan Turing

• I believe that at the end of the century the
  use of words and general educated opinion will
  have altered so much that one will be able to
  speak of machines thinking without expecting to
  be contradicted.

51
Biography - Alan Turing

• 1934 Graduated from Kings College, Cambridge
  with a distinguished degree
• 1935 Elected a Fellow at Kings
• 1938 Received his Ph.D. from Princeton
• During WWII worked at Bletchley Park, his work
  there was kept secret until the 1970s
• 1945-1947 Worked on the design of ACE
  (Automatic Computing Engine) at the National
  Physical Laboratory

52
Biography - Alan Turing

• 1949 Became deputy director of the computing
  laboratory at the University of Manchester
• 1952-1954 Worked on mathematical biology
• 1954 Died of cyanide poisoning from a
  half-eaten apple, death ruled a suicide

53
Achievements - Alan Turing

• Often considered to be the father of modern
  computer science
• Turing Test
• Turing Machine
• Church-Turing Thesis
• Worked at Bletchley Park during WWII
• Invented an electromechanical machine which could
  find settings for Enigma
• Created one of the first designs for a stored
  program computer

54
Trivia - Alan Turing

• Said to have taught himself to read in three
  weeks
• At age 14, rode a bike 60 miles to attend his
  first day at Sherborne School
• Was gay during a time when it was illegal, many
  believe this led to his security clearance being
  revoked, and possibly his death
• Was forced to undergo hormonal treatment in lieu
  of prison

55
Conclusions

• This is only a small sampling of people who have
  contributed greatly to the field of computer
  science. We would like to thank the many others
  who havent been recognized, but have given
  greatly to our pool of knowledge. The future is
  bright, there are many active fields of research,
  and we look forward to acknowledging other
  pioneers in computer science.

56
References

• Computer Science Prof Cook. Cook, Stephen.
  November 2005 lthttp//www.cs.toronto.edu/DCS/Peopl
  e/Faculty/sacook.htmlgt
• Dewdney, A.K. The New Turing Omnibus. New York
  Henry Holt and Company, 1989.
• Don Knuths Home Page. Knuth, Donald. November
  2005 lthttp//www-cs-faculty.stanford.edu/knuth/gt
• Knuth, Donald. The Art of Computer Programming.
  United States of America Addison-Wesley Pub Co,
  1997.
• Knuth, D. E. and Bendix, P. B. "Simple Word
  Problems in Universal Algebra." In Computational
  Problems in Abstract Algebra (Proc. Conf.,
  Oxford, 1967). Pergamon Press, pp. 263-297, 1970.
  
• Shasha, Dennis Elliott. Out of their minds the
  lives and discoveries of 15 great computer
  scientists. New York Copernicus, 1995.
• Winston, Patrick Henry. LISP. Reading
  Addison-Wesley Publishing Company, 1984.
• Multiple Articles, November 2005
  lthttp//wikipedia.orggt