Counting
 Man started off by
counting on his digits
 Needed ways to measure
months and seasons in order
to perform festivals and
ceremonies
Primitive Calendar
 Stonehenge
 Home for thousands of years to ceremonial and religious
events involving the summer solstice
The Abacus:
 The First “Automatic” Computer
 The abacus
 first attempt at automating the counting process.
 The abacus is not really an automatic machine it is
more a machine which allows the user to remember
his current state of calculations while performing
more complex mathematical operation.
The Antikythera mechanism
 Analog computer used to calculate Astronomical
positions.
Forefathers of Computing
 Forefathers of Modern Computers
Charles Babbage
Gottfried Wilhelm
Blaise Pascal
The First Mechanical
Calculator
 Pascal’s Gear System
 A one tooth gear engages its single tooth with a tenteeth gear once every time it revolves; the result will
be that it must make ten revolutions in order to
rotate then ten-teeth gear once.
 This is the way that an odometer works for counting
kilometers. The one tooth gear is large enough so that
it only engages the next size gear after 1km has
passed.
The Difference Engine
 Never built
 Steam-driven
 Fully automatic
 Next idea was the Analytical Engine
The Conditional
 Babbage’s Conditional
 The conditional point allows us to check to see what the
current value of “S” is. If “s” is greater than “3”, then we
want the computer to output the value of “s” (4 in this
case.) If “s” is less than or equal to 3, then we want the
computer to output the value “0”
Hermann Hollerith’s Tabulating Machine
 This machine was so successful that Hollerith started
a firm to market it which later became known as IBM
Binary Representations
 Numbers can be converted to decimal to adding
together the values of the holes, given that the first
hole = 1 and the second 2, etc.
 For example, 26=2^5+2^3+2^1+2^0
 Holes represent an “on” signal.
 With 6 holes permissible, 2^6 numbers possible.
Harvard Mark I
 Grace M. Hopper working on the
Harvard Mark-I, developed by
IBM and Howard Aiken. The
Mark-I remained in use at
Harvard until 1959, even though
other machines had surpassed it
in performance, providing vital
calculations for the navy in
World War II.
Alan Turing
 Sample Turing Machine
 Problem: Output a 1 if 3 or more ones in a row
encountered; otherwise )
ENIAC
John Von Neumann
 The Von Neumann Machine
 Data and program can be stored in the same space. Thus, the
machine itself can alter either its program or its internal data.
 Conditional goto’s to other points in the code
 Von Neumann worked with Mauchly and Eckert on the design
for EDVAC
 Also a contributor to the fields of game theory and cellular
automata
John Von Neumann
EDVAC
Advances in the 1950’s
 Transistors
 Freedom from vacuum tubes, which were extremely
bulky
 Integrated Circuits

Allowed the placement of many transistors into a small area.
 Both these advances enables machines to become
smaller and more economical to build and maintain
The Altair
 Bill Gates and Paul Allen in 1975 approached Ed
Roberts if MITS, the company who developed the
Altair, and promised to deliver the BASIC complier.
 They did so and
from the sale
Microsoft was born
Creation of Microsoft
 BASIC- Beginner’s All-Purpose Symbolic Instruction
Code
 Developed by Kemeny and Kurtz in 1964. two
mathematicians at Dartmouth
 Simple, easy-to-understand syntax allowed students to
quickly learn it.
 Provided ease of programming and easier debugging
than machine code or assembly
Other Languages
 FORTRAN
 FORmula Translator
 Used for science, math, & engineering
 PASCAL
 Developed by Niklaus Wirth in the 60’s
 Disciplined approach to structure and data description
 COBOL
 Common Business Oriented Language

Data description stored separately from the pgram.

Derivative of ALGOL
It and its decendant’s very popular today for system programming
 C

The PC Explosion
 IBM
 Acorn released under the unassuming name PC in 1981
 1984, 286-AT
 Whole Host of clones introduced & Compaq releases a portable
 Apple




Apple II, 1977
Apple III, 1980
Lisa, 1983; first machine with a mouse and graphical user interface
Macintosh introducted in 1984
 Other
 TRS-80 from Radio Shack 1977
 Commodore PET 1980’s
 1981, journalist Adam Osborn commissions design of Osborne I which used
CP/M
Bill & Steve Before Microsoft
PCs Today
 Fast
 Graphical User Interfaces (GUI)
 Allows you to use a mouse to control the computer
 Can run thousands of different sets of instructions
(programs)
The Web
 The Web can be used for:
 Looking up information on publications
 Shopping for books, computers, or CD’s
 Investigating staff or research at universities
 Downloading pictures, games, or other files
 The Web (World Wide Web) was developed at CERN lab
in Zurich, Switzerland/
 Requires a client program (such as NetScape or Lynx) and a
server (HTTP) to send information to the client
Internet
 New form of communicating
 2 things needed to view the internet
 Internet connection
 Browser