### Computer History

**Factors**

• Speed

• Accuracy

• Automatic

• Versatility

• Storage

• Reduction of Cost

• Intelligent

**Stick and Stones**

• People in early times used their fingers and made marks on cave walls to help themselves remember and count. They used STICKS and STONES to keep track of things.

**Abacus – 3000 BC**

• A counting machine called ‘ABACUS’, was used by people in China, Greece, and Middle East to calculate. Beads were Bmoved back and forth along parallel rods to add and subtract large numbe.

**John Napier (1550 – 1617)**

• Scottish landowner known as a mathematician, physicist, astronomer and astrologer.

• invented Napier’s Bones.

### Computer History pdf

**Napier’s Bones – 1617**

• Napier’s Invention was used to multiply and divide numbers.

• It was the first machine to use the decimal point.

**William Oughtred (1574 – 1660)**

• English Mathematician (was one of the world’s great mathematicians).

• invented the slide rule.

• introduced the ‘×’ symbol for multiplication as well as the abbreviations ‘sin’ and ‘cos’ for the sine and cosine functions.

**Slide Rule – 1622**

• Slide rule was similar to a calculator and could accurately add numbers up to three digits.

**Blaise Pascal (1623 – 1662)**

• French Mathematician, physicist, inventor, writer and catholic philosopher

• invented the pascaline

**Pascaline – 1642**

• Pascal developed a calculator called the ‘Arithmatique’ or ‘Pascaline’. Pascal’s device used a series of toothed wheels, which were turned by hand and which could handle numbers up to 999,999.999. Pascal’s device was also called the ‘numerical wheel calculator’ and was one of the world’s first

mechanical adding machines.

**Gottfried Wilhelm Leibnitz (1646 – 1716)**

• German mathematician and philosopher.

• improved Pascal’s invention.

• invented the First Calculator called the Step Reckoner (or Stepped Reckoner) was a digital mechanical calculator or called now the Leibnetz wheel.

### Computer History in English

**Step Reckoner or Leibnitz Wheel – 1672 – 1694**

• Step Reckoner or Leibnitz wheel was a digital mechanical calculator around 1672 and completed in 1694. It was the first

calculator that could perform addition, subtraction, multiplication and division.

**Charles Babbage (1791 – 1871)**

• English inventor.

• taught math at Cambridge University.

• invented a viable mechanical computer equivalent to modern digital computers called the difference and analytical engine.

• Called the Father of modern computer.

**Difference Engine -1833**

• Babbage first computer.

• a mechanical device that could perform simple mathematical calculations.

• automatic, mechanical calculator designed to tabulate polynomial functions.

**Analytical Engine – 1834**

• Babbage ‘s second computer.

• used binary system.

• punched cards as input.

• intended to combine its numerical qualities as though they were letters or other symbols.

**August Ada Byron King (1815 – 1852)**

• Created a program for the (theoretical) Babbage analytical engine which would have calculated Bernoulli numbers.

• Widely recognized as the first programmer.

**ENIAC – 1946**

• Electronic Numerical Integrator and Computer.

• World’s first digital computer.

• Massive machine was world’s first large-scale electronic general purpose digital computer.

• Filled entire room & calculate in two hours.

**UNIVAC – 1951**

• Universal Automatic Computer.

• was the first commercial computer produced in the United States.

**Microcomputer – 1981**

• IBM introduced the 1 st personal

computer.

• The smallest type of computer designed for a single user.

**Computers Today**

• Computers getting smaller and more powerful.

• Computers that are so tiny to fit in your hand.

**Reference Book :**

• *Text Book –*

– Introduction to Computers – Peter Norton (pdf)

**Collected :**

Department of CSE,

Varendra University