Four Basic Period of

Computer History

•Pre-mechanical Age•Mechanical Age• Electromechanical Age• Electronic Age

Pre-Mechanical Age(3000B.C. - 1450 A.D.)

Writing and Alphabets

•Petroglyths (signs or simple figures carved in rock)

Petroglyths

Cave painting from Lascaux, France(15,000-10,000 B.C.)

• Ideographs (symbols to represent ideas and concept)

Mayan Ideograph

• Cuneiform – the first true written language and the first real information system. (coo-nay-eh-form)• Star – heaven or God

Cuneiform

• At around 2000 BC the Phoenicians created symbols that expressed single syllables and consonants (the first true alphabet)• Greek adopted the Phoenician

alphabet and added vowels • Romans gave the letters Latin name

to create the alphabet we use today.

Papers and pens• Sumerians – stylus and wet clay• Egyptians – papyrus plants (2600 BC)• Chinese – made paper from rags

(100 AD)

Stylus and wet clay

Papyrus Plant

Chinese

Books and Libraries(permanent storage device)

• Mesopotamia – religious leaders kept the earliest book• Egyptians – kept scrolls• Greeks – (600 BC) fold sheets of

Papyrus vertically into leaves and bind them together.

First Numbering System

• Egyptian – Vertical lines (|)for numbers 1 – 9- U or O – 10- coiled rope – 100- lotus blossom for 1000

• Hindus – (100 – 200 AD) 9 digit numbering • 875 AD the concept of zero was developed.

The First Calculator• Abacus – was man’s first recorded

adding machine. Invented in Babylonia and popularized in China.

Mechanical Age

(1450 – 1840)

First Information Explosion• Johann Guttenberg – Movable metal-

type printing process in 1450.

The first general purpose computers

• John Napier – (1614) a Baron of Merchiston, Scotland invented LOGS (Logarithm).

• LOGS – allows multiplication and division to be reduce in addition and subtraction.

• 1614 – Arabian Lattice – lays out a special version of the multiplication tables on a set of four-sided wooden rods.(multiply, divide large numbers and find square and cube root)

John NapierNapier’s Bone

• Wilhelm Shickard – 1623 - (Professor at University of Tubingen, Germany) – invented the first mechanical calculator that can work with six digits and can carries digits across columns.

• William Oughtred – (1575 – 1660) invented the slide rule.

• Blaise Pascal (1642) – invented the Pascaline. (made of clock gears and levers) that could solve mathematical problems like addition and subtraction.

• Gottfried Leibniz – (1617) invented Stepped Reckoner that could multiply 5 digit and 12 digit numbers yielding up to 16 digit numbers.

Stepped Reckoner

• Joseph-Marie Jacquard (1801) developed the automatic loom (weaving loom) that was controlled by punched cards.

• Charles Xavier Thomas de Colmar -1820 – developed Arithmometer (the first mass produced calculator)

• Charles Babbage – invented the difference engine (1821) and analytical engine (1832).

- Father of modern computer.

Difference Engine Analytical Engine

• Lady Ada Augusta Lovelace Byron – 1842 – the first computer programmer.

Electromechanical Age(18-40 1940)

The Beginning of Telecommunications

• Voltaic Battery – first electric battery known as voltaic pile

- invented by Alessandro Volta

• Telegraph Samuel F.B. Morse – conceived of his version of an Electromagnetic Telegraph (1832)

Morse Code

• Telephone and Radio Alexander Graham Bell – 1879 - developed

the first working telephone.

Guglielmo Marconi – 1894 – (RADIO) discovered that electrical waves travel through space and can produce and effect far from the point at which it originated.

• George Boole – 1852 – developed the binary algebra known as Boolean Algebra

Electromechanical Computing

• Pehr and Edward Scheutz – 1853 - completed a Tabulating Machine, capable of processing fifteen digit numbers, printing out result and rounding off to eight digits.

Dorr Felt – 1885 – devises the comptometer, a key driven adding and subtracting calculator.Comptograph containing a built in printer

Comptometer Comptograph

Herman Hollerith – father of information processing.

Punched Card – provided computer programmers with a new way to put information into their machines.

He founded the Tabulating Machine Company , later became the Computer Tabulating Recording Company and International Business Machines Corporation (IBM)

Herman Hollerith Tabulating Machine

Otto Shweiger – 1893 – invented the first efficient four function calculator called Millionaire.

Lee de Forest – 1906 – developed vacuum tubes This is important for it provided

electrically controlled switch.

Electronic Age(1941 – present)

Konrad Zuse – 1941 – built the first programmable computer called Z3.

Howard Aiken – 1942 – developed Mark I the first stored program computer.

John Atanasoff and Clifford Berry – 1942 – completed the first all electronic computer called ABC or Atanasoff-Berry Computer

John Atanasoff Clifford Berry