EVOLUTION OF COMPUTERS. The earliest foundations of what would become computer science predate the invention of the modern digital computer. Start of.

EVOLUTION OF COMPUTERS

• The earliest foundations of what would become computer science predate the invention of the modern digital computer.

• Start of modern science (computer science) is traced way back to the age when man still dwelled in caves or forests and lived in groups for protection and survival from harsh conditions.

• Many of these groups of people practiced primitive religions; worshiping the sun, trees, moon, and sacred animals. “Man started by counting on his fingers. He needed ways to measure months and seasons in order to perform religious festivals and ceremonies at a correct time.”

REMEMBER!!!• WHAT IS A COMPUTER?• The word ‘computer’ was derived from

two Latin words; ‘com’, which means ‘together’ and ‘putare’, which may means ‘add, calculate, count, or estimate’.

• The ABACUS developed in 3000 BC by Chinese

• The abacus was so successful that its use spread from China to many other countries. .

• Abacus was not an automatic machine, but rather a machine that allowed the user to remember his or her current state of calculation, while performing more complex mathematical calculations. It’s a memory aid for the user making mental calculations and not the mathematical calculating machines as we know.

• The Abacus uses sliding beads that are divided into two by a center bar. The top is “Heaven” where each of two beads is 5 when moved to the center bar. The bottom is “earth”, where each of the five beads is worth 1 when moved to the center bar.

• HOW ABOUT 4449610• 1000023• ILLUSTRATE TO THE CLASS

JOHN NAPIER AND THE NAPIER RODS OR BONES (1614)

• John Napier was a Scottish mathematician who invented a set of Logarithms for calculations that enabled the reduction of difficult and tedious multiplication to addition of table entries.

• The Napier bones or rods consisted of strips of wood with the left edge (vertically) consisting of 9 squares (1 to 9). Each square accept the top one is diagonally divided. Therefore, the first square of each rod holds a single digit and the other squares hold this numbers double, triple, quadruple and son on until the last square holds nine times the number in the top square. The digits of each product are written in the two halves (triangles) created by the diagonal line: zero is always on top.

multiply 245 by 3. Of course the product of 245 by 3 is 735

HOW COULD NAPIER MULTIPLY THIS BY ADDITION?

HOMEWORK: EXECUTE THE DIVISION BASED ON NAPIER BONES…….

REMENBER: MULTIPLICATION = ADDITION

DIVISION = SUBTRACTION

WILLIAM OUGHTRED AND THE SLIDE RULE (1630)

• The SLIDE RULE was invented in ENGLAND by William Oughtred and it was based on the emerging work of John Napier. It was a ruler shaped or structured device operated by sliding a set of transparent plastic slides. The scales on the slide rule are logarithmic; that’s to say, the spacing between divisions (the lines on the scale) became closer together as the value increased.

• The Slide Rule did not indicate decimal places. Decimal places where done by the user through estimation “common Sense”. The Slide Rule was used by pilots and ships up to the early 1970’s when it was made obsolete by electronic computers.

BLAISE PASCAL AND THE ADDING MACHINE (1642)

• PASCAL BLAISE, a French Engineer invented the first commercial calculator and named it the “ADDING MACHINE” (also known as the 1st calculator to the world). It was capable of doing additions and subtractions of only 8 digits.

• GOTFRIED VON LEIBNITZ created a better calculator (known as the LEIBNITZ CALCULATOR) that was capable of doing extra tasks of multiplication, division as well as evaluating square roots.

• This period can effectively be referred to as the MECHANICAL COMPUTER ERA (1624 – 1890).

LEIBNITZ CALCULATOR

JOSEPH JACQUARD in 1810

• He constructed a Loom that used a series of Punched Cards to control the thread pattern. The cards carried weaving instructions for the Loom; Punched Cards were joined to form an infinite loop that represented the repetition pattern used for cloth and rug production.

HERMAN HOLLERITH 1890• HERMAN HOLLERITH made further

improvements to the calculator by producing the TABULATION MACHINE.

• History has it that the US 1880 census took 7 years to tabulate rendering the final result or figure obsolete. However Herman’s machine counted the entire population data in only 6 weeks.

• Based on the success of his invention, Hollerith and friends formed a company that later became the popular IBM (INTERNATIONAL BUSINESS MACHINE).

CHARLES BABBAGE: (DIFFERENCE AND ANALYTICAL ENGINE)

• The concept of today's computers (Input - Process - Output) was first visualized by Charles Babbage in 1834 in England.

• In less than two years, Babbage had sketched out many of the recognizable features of the modern computer. He called it the Analytical Engine. This machine would be the first computer ever capable of storing programmed information. His idea for the Analytical Engine consisted of 4 parts: an input device, a storage device, a mill (processing unit) and an output device.

COMPUTER GENERATIONS• History of computer development is often

referred to in reference to the different generations of computing devices.

• A generation means or refers to an improvement in the product development process (advancement of new computer technology). Each new generation has seen a smaller and more advanced circuitry, smaller computers, faster speeds, cheaper and more efficient and reliable machines.

FIRST GENERATION: THE ERA OF THE VACUUM TUBES (1940 – 1956)

• The first all electronic computers used vacuum tubes for the internal circuitry and magnetic drums for memory.

• Magnetic Drums were metal cylinders coated with non – oxide material to store data and programs. Magnetic drums are no longer the primary storage but peripheral or auxiliary storage devices. The drums were rotated at high speed of about 3000 rpm

CHARACTERISTICS OF FIRST GENERATION COMPUTERS

• 1st generation computers used a lot of electricity (200kwts)

• Generated a lot of heat which was often the cause of malfunction. They had to be cooled down with the help of gigantic fans

• Based on machine language to perform operations• These machines could only solve one problem at a

time• They had limited primary memory (as they used

magnetic drums for memory)• Used Vacuum tubes for their circuitry (or internal

operations)• Used Punched cards for Input and Output• Very expensive to develop, maintain and purchase

EXAMPLE OF 1ST GENERATION COMPUTERS

• ENIAC (Electronic Numerical Integrator and Computer) is referred to as the worlds’ first digital computer. It weighed 30 tons and used 200 kilowatts of electricity. This computer consisted of 1800 vacuum Tubes, 1500 relays and hundreds of resistors and inductors. The ENIAC cost a staggering $487000.

• EDVAC (Electronic Discrete Variable Automatic Computer) and the UNIVAC (Universal Automatic Calculator). It was programmed by Grace Hopper.

ENIAC

EDVAC